Sports Nutrition Practice Exam

Question 1 Sports Nutrition

What are electrolytes and why do athletes need them?

Sodium is the primary electrolyte lost in sweat (average 500–1500 mg/L). It regulates fluid balance, nerve impulses, and muscle contractions. Athletes exercising >1 hour, especially in heat, should replace sodium to prevent hyponatremia and maintain performance. Electrolytes are minerals that carry an electrical charge: sodium, potassium, chloride, calcium, magnesium. They regulate fluid balance, nerve function, and muscle contraction. Athletes lose them through sweat, especially sodium (500–1500 mg/L of sweat). Caffeine reduces perceived exertion, increases alertness, enhances endurance performance (3–5%), and may improve strength and power output. Effective dose: 3–6 mg/kg body weight, consumed 30–60 minutes before exercise. Creatine is a naturally occurring compound stored as phosphocreatine in muscles. It regenerates ATP during short, high-intensity efforts (the phosphagen system). Supplementing increases muscle creatine stores by 20–40%, improving power output and recovery.

Question 2 Sports Nutrition

What is the biological value (BV) of a protein?

A caloric deficit means consuming fewer calories than you expend. It is necessary for fat loss. A moderate deficit of 300–500 kcal/day below TDEE promotes fat loss while preserving muscle mass (with adequate protein and resistance training). Yes. Creatine monohydrate is one of the most studied and safest supplements available. Research spanning decades shows no adverse effects on kidney or liver function in healthy individuals at recommended doses. Biological value measures the proportion of absorbed protein that is retained and used by the body. Whole egg has a BV of 100 (reference), whey protein ~104, casein ~77, and soy ~74. The standard protocol is a loading phase of 20 g/day (split into 4 doses) for 5–7 days, followed by a maintenance dose of 3–5 g/day. Alternatively, taking 3–5 g/day without loading saturates muscles in ~28 days.

Question 3 Sports Nutrition

What is a caloric surplus and when is it used?

Carb loading is a strategy to maximize glycogen stores before endurance events lasting >90 minutes. The modern approach involves eating 8–12 g carbs/kg/day for 1–3 days before competition while tapering training. Team sports require 5–7 g carbs/kg/day, 1.4–1.7 g protein/kg/day, with emphasis on pre-game carb loading and halftime refueling. Hydration is critical as games involve intermittent high-intensity efforts. Post-game recovery should focus on protein + carbs within 2 hours. A caloric surplus means consuming more calories than you expend. It is used for muscle gain (bulking). A moderate surplus of 250–500 kcal/day above TDEE promotes muscle growth while minimizing fat gain. A complete protein contains all nine essential amino acids in adequate amounts: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Examples include meat, fish, eggs, dairy, soy, and quinoa.

Question 4 Sports Nutrition

What is a caloric deficit and when is it used?

A caloric deficit means consuming fewer calories than you expend. It is necessary for fat loss. A moderate deficit of 300–500 kcal/day below TDEE promotes fat loss while preserving muscle mass (with adequate protein and resistance training). TEF is the energy required to digest, absorb, and process nutrients. Protein has the highest TEF (~20–30% of calories consumed), followed by carbohydrates (~5–10%) and fat (~0–3%). TEF accounts for ~10% of total daily energy expenditure. Omega-3s (EPA and DHA) are essential polyunsaturated fatty acids found in fatty fish, flaxseed, and walnuts. They reduce inflammation, support cardiovascular health, may improve recovery, and have been linked to reduced exercise-induced muscle soreness. Beta-alanine is an amino acid that increases intramuscular carnosine levels, which buffers hydrogen ions during high-intensity exercise. It reduces fatigue during efforts lasting 1–4 minutes. Common dose: 3–6 g/day. May cause harmless tingling (paresthesia).

Question 5 Sports Nutrition

Does eating carbs at night cause fat gain?

No. Total daily calorie intake, not timing, determines fat gain. Carbs at night can actually improve sleep quality (via serotonin/melatonin production) and may be beneficial for morning training. What matters is the overall energy balance throughout the day. Collagen is the most abundant protein in the body, found in tendons, ligaments, skin, and cartilage. Supplementing with 10–15 g collagen peptides + vitamin C before exercise may support tendon and ligament health. However, it is not a complete protein and should not replace whey/casein. Caffeine reduces perceived exertion, increases alertness, enhances endurance performance (3–5%), and may improve strength and power output. Effective dose: 3–6 mg/kg body weight, consumed 30–60 minutes before exercise. Saturated fats have no double bonds between carbon atoms (solid at room temperature, e.g., butter). Unsaturated fats have one or more double bonds (liquid at room temperature, e.g., olive oil). Unsaturated fats are generally considered healthier.

Question 6 Sports Nutrition

How do you calculate macronutrient ratios?

Diet breaks are planned periods (1–2 weeks) of eating at maintenance calories during a fat loss phase. Refeeds are shorter (1–2 days) periods of increased carbohydrate intake. Both may help counteract metabolic adaptation, reduce psychological stress, and restore leptin levels. A caloric surplus means consuming more calories than you expend. It is used for muscle gain (bulking). A moderate surplus of 250–500 kcal/day above TDEE promotes muscle growth while minimizing fat gain. First determine calorie needs (TDEE). Then set protein (1.6–2.2 g/kg), fat (20–35% of calories), and fill remaining calories with carbohydrates. Example for 80 kg athlete at 3000 kcal: protein 160 g (640 kcal), fat 83 g (750 kcal), carbs 403 g (1610 kcal). No. Total daily calorie intake, not timing, determines fat gain. Carbs at night can actually improve sleep quality (via serotonin/melatonin production) and may be beneficial for morning training. What matters is the overall energy balance throughout the day.

Question 7 Sports Nutrition

What is the role of potassium in athletic performance?

No. Total daily calorie intake, not timing, determines fat gain. Carbs at night can actually improve sleep quality (via serotonin/melatonin production) and may be beneficial for morning training. What matters is the overall energy balance throughout the day. Potassium helps regulate fluid balance, muscle contractions, and nerve signals. It works with sodium to maintain cellular hydration. Deficiency can cause muscle cramps and weakness. Athletes need 3500–4700 mg/day from foods like bananas, potatoes, spinach, and avocados. Endurance athletes: 1.2–1.4 g/kg/day to repair tissue and support immune function. Strength athletes: 1.6–2.2 g/kg/day to support muscle growth and repair. Both benefit from distributing protein evenly across 4–5 meals. Micronutrients are vitamins and minerals required in small amounts for essential bodily functions. They do not provide energy but are critical for metabolism, immune function, bone health, and hundreds of enzymatic reactions.

Question 8 Sports Nutrition

What is nutrient timing?

No. Supplements are not required for muscle building. A well-planned diet can provide all necessary nutrients. However, creatine, protein powder, and vitamin D may be convenient and beneficial when dietary intake is insufficient. Supplements should supplement, not replace, real food. Pre-workout supplements typically contain a blend of caffeine, beta-alanine, citrulline, creatine, and/or nitric oxide precursors. They aim to increase energy, focus, blood flow, and performance. Effects vary by ingredient quality and dosage. Nutrient timing is the strategic consumption of specific nutrients at specific times relative to exercise to optimize performance, recovery, and body composition. Key periods include pre-workout, intra-workout, and post-workout nutrition. Hyponatremia is dangerously low blood sodium levels (<135 mmol/L), often caused by drinking excessive water without adequate sodium replacement during prolonged exercise. Symptoms include nausea, confusion, seizures; can be fatal.

Question 9 Sports Nutrition

What is vitamin D's role in athletic performance?

Vitamin D supports calcium absorption, bone health, immune function, and muscle function. Deficiency is linked to increased injury risk, impaired recovery, and reduced performance. Many athletes are deficient, especially those training indoors. Recommended: 1000–2000 IU/day. Plant proteins can be equally effective if consumed in sufficient quantity and variety to provide all essential amino acids. Plant proteins are generally lower in leucine and may have lower digestibility (DIAAS). Combining sources (e.g., rice + pea protein) creates a complete amino acid profile. The anabolic window is the supposed 30–60 minute post-exercise period when nutrient uptake is enhanced. Current research suggests this window is wider than originally thought (several hours), and total daily protein intake matters more than precise timing. Zinc supports immune function, protein synthesis, testosterone production, and wound healing. Exercise increases zinc loss through sweat and urine. RDA: 11 mg (males), 8 mg (females). Found in meat, shellfish, legumes, and seeds.

Question 10 Sports Nutrition

What is the recommended fat intake for athletes?

Electrolytes are minerals that carry an electrical charge: sodium, potassium, chloride, calcium, magnesium. They regulate fluid balance, nerve function, and muscle contraction. Athletes lose them through sweat, especially sodium (500–1500 mg/L of sweat). Potassium helps regulate fluid balance, muscle contractions, and nerve signals. It works with sodium to maintain cellular hydration. Deficiency can cause muscle cramps and weakness. Athletes need 3500–4700 mg/day from foods like bananas, potatoes, spinach, and avocados. Isotonic: same osmolality as blood, balanced fluid and energy replacement (most sports drinks). Hypotonic: lower osmolality, faster fluid absorption, less energy (e.g., diluted juice). Hypertonic: higher osmolality, more energy but slower absorption (e.g., fruit juice, recovery drinks). Athletes should consume 20–35% of total daily calories from fat. Intake below 20% can impair hormone production and fat-soluble vitamin absorption. Emphasis should be on unsaturated fats.

Question 11 Sports Nutrition

Why is iron important for athletes?

This is largely a myth. Meal frequency has minimal impact on metabolic rate when total calorie and protein intake are equated. The thermic effect of food is determined by total intake, not meal frequency. Eating 3–6 meals per day based on preference and schedule is fine. Gut training involves practicing race-day nutrition during training to improve gastrointestinal tolerance and nutrient absorption. The gut can be trained to absorb more carbohydrate (up to 90 g/hour) and tolerate foods during exercise with consistent practice. Iron is essential for hemoglobin (oxygen transport in blood) and myoglobin (oxygen storage in muscle). Iron deficiency impairs endurance performance, causes fatigue, and is common in female athletes and endurance athletes. RDA: 8 mg (males), 18 mg (females). Whey protein is a fast-digesting, complete protein derived from milk during cheese production. It is rich in BCAAs (especially leucine) and has a high biological value. Types include concentrate (~80% protein), isolate (~90%), and hydrolysate (pre-digested).

Question 12 Sports Nutrition

What should athletes eat during prolonged exercise?

Team sports require 5–7 g carbs/kg/day, 1.4–1.7 g protein/kg/day, with emphasis on pre-game carb loading and halftime refueling. Hydration is critical as games involve intermittent high-intensity efforts. Post-game recovery should focus on protein + carbs within 2 hours. TDEE = BMR × Activity Factor. BMR (Basal Metabolic Rate) can be estimated using equations like Mifflin-St Jeor. Activity factors: sedentary (1.2), light (1.375), moderate (1.55), active (1.725), very active (1.9). During exercise lasting >60 minutes, consume 30–60 g of carbohydrates per hour from easily digestible sources (sports drinks, gels, bananas). For events >2.5 hours, intake can be increased to up to 90 g/hour using glucose + fructose combinations. Beta-alanine is an amino acid that increases intramuscular carnosine levels, which buffers hydrogen ions during high-intensity exercise. It reduces fatigue during efforts lasting 1–4 minutes. Common dose: 3–6 g/day. May cause harmless tingling (paresthesia).

Question 13 Sports Nutrition

What is collagen protein and is it beneficial for athletes?

Masters athletes need higher protein (1.6–2.2 g/kg/day) due to anabolic resistance, adequate vitamin D and calcium for bone health, omega-3s for inflammation management, and may benefit from creatine supplementation. Recovery takes longer, so post-workout nutrition timing is more important. The Randle cycle (glucose-fatty acid cycle) describes the competition between glucose and fatty acids for oxidation. When fat availability is high, fat oxidation increases and glucose oxidation decreases, and vice versa. This is relevant for understanding fuel selection during exercise. Glutamine is the most abundant amino acid in the body, important for immune function and gut health. Intense exercise depletes glutamine levels. Supplementation (5–10 g/day) may support immune function in heavily training athletes, but evidence for muscle-building benefits is weak. Collagen is the most abundant protein in the body, found in tendons, ligaments, skin, and cartilage. Supplementing with 10–15 g collagen peptides + vitamin C before exercise may support tendon and ligament health. However, it is not a complete protein and should not replace whey/casein.

Question 14 Sports Nutrition

What is the ketogenic diet?

Micronutrients are vitamins and minerals required in small amounts for essential bodily functions. They do not provide energy but are critical for metabolism, immune function, bone health, and hundreds of enzymatic reactions. Dietary nitrate (from beetroot juice) is converted to nitric oxide, which improves blood flow, reduces oxygen cost of exercise, and enhances muscle efficiency. It can improve endurance performance by 1–3%. Effective dose: ~6–8 mmol nitrate taken 2–3 hours pre-exercise. The ketogenic diet is a very low-carb, high-fat diet (typically <50 g carbs/day) that forces the body to use fat/ketones as primary fuel. It may benefit ultra-endurance athletes but generally impairs high-intensity performance due to reduced glycogen availability. Digestible Indispensable Amino Acid Score evaluates protein quality based on the digestibility of individual essential amino acids. It replaced the older PDCAAS method. Scores >100 are excellent (e.g., milk, eggs); plant proteins typically score lower.

Question 15 Sports Nutrition

What are the benefits of caffeine for exercise?

Caffeine reduces perceived exertion, increases alertness, enhances endurance performance (3–5%), and may improve strength and power output. Effective dose: 3–6 mg/kg body weight, consumed 30–60 minutes before exercise. Top sources include chicken breast, lean beef, fish (salmon, tuna), eggs, Greek yogurt, cottage cheese, whey protein, and plant sources like tofu, tempeh, and lentils. Quality is determined by amino acid profile and digestibility (DIAAS score). Potassium helps regulate fluid balance, muscle contractions, and nerve signals. It works with sodium to maintain cellular hydration. Deficiency can cause muscle cramps and weakness. Athletes need 3500–4700 mg/day from foods like bananas, potatoes, spinach, and avocados. Essential amino acids (EAAs) cannot be synthesized by the body and must come from diet (9 total). Non-essential amino acids can be produced by the body. Conditionally essential amino acids (e.g., glutamine) become essential during illness or stress.

Question 16 Sports Nutrition

What is the importance of gut training for athletes?

Zinc supports immune function, protein synthesis, testosterone production, and wound healing. Exercise increases zinc loss through sweat and urine. RDA: 11 mg (males), 8 mg (females). Found in meat, shellfish, legumes, and seeds. Gut training involves practicing race-day nutrition during training to improve gastrointestinal tolerance and nutrient absorption. The gut can be trained to absorb more carbohydrate (up to 90 g/hour) and tolerate foods during exercise with consistent practice. Simple carbs (monosaccharides, disaccharides) are quickly digested and raise blood sugar rapidly (e.g., fruit, sugar, honey). Complex carbs (polysaccharides) digest more slowly and provide sustained energy (e.g., oats, rice, potatoes). Sodium is the primary electrolyte lost in sweat (average 500–1500 mg/L). It regulates fluid balance, nerve impulses, and muscle contractions. Athletes exercising >1 hour, especially in heat, should replace sodium to prevent hyponatremia and maintain performance.

Question 17 Sports Nutrition

What is beta-alanine?

The standard protocol is a loading phase of 20 g/day (split into 4 doses) for 5–7 days, followed by a maintenance dose of 3–5 g/day. Alternatively, taking 3–5 g/day without loading saturates muscles in ~28 days. Beta-alanine is an amino acid that increases intramuscular carnosine levels, which buffers hydrogen ions during high-intensity exercise. It reduces fatigue during efforts lasting 1–4 minutes. Common dose: 3–6 g/day. May cause harmless tingling (paresthesia). The three macronutrients are protein, carbohydrates, and fats. Each provides energy: protein and carbs yield ~4 kcal/g, while fat yields ~9 kcal/g. Omega-3s (EPA and DHA) are essential polyunsaturated fatty acids found in fatty fish, flaxseed, and walnuts. They reduce inflammation, support cardiovascular health, may improve recovery, and have been linked to reduced exercise-induced muscle soreness.

Question 18 Sports Nutrition

What is the difference between whey concentrate, isolate, and hydrolysate?

General guideline: at least 3–4 liters per day for active individuals. A more precise method: drink enough to maintain pale yellow urine. During exercise, aim for 400–800 mL/hour depending on sweat rate and conditions. Concentrate: 70–80% protein, contains some fat and lactose. Isolate: 90%+ protein, minimal fat/lactose, faster absorption. Hydrolysate: pre-digested for fastest absorption, most expensive. All are effective; isolate is best for lactose-intolerant individuals. Beginners can build muscle in a deficit (body recomposition). Intermediate athletes need a slight surplus for muscle gain. Advanced athletes need precise nutrition with small surpluses. Training status also affects glycogen utilization efficiency and fat oxidation capacity. Vitamin D supports calcium absorption, bone health, immune function, and muscle function. Deficiency is linked to increased injury risk, impaired recovery, and reduced performance. Many athletes are deficient, especially those training indoors. Recommended: 1000–2000 IU/day.

Question 19 Sports Nutrition

How much protein per day is generally recommended for athletes?

Pre-workout supplements typically contain a blend of caffeine, beta-alanine, citrulline, creatine, and/or nitric oxide precursors. They aim to increase energy, focus, blood flow, and performance. Effects vary by ingredient quality and dosage. Carbohydrates are the body's preferred fuel source during moderate-to-high intensity exercise. They are stored as glycogen in muscles and liver, providing readily available energy for athletic performance. Most sports nutrition guidelines recommend 1.2–2.0 g of protein per kg of body weight per day for athletes, depending on the sport and training intensity. Endurance athletes need ~1.2–1.4 g/kg; strength athletes need ~1.6–2.0 g/kg. A pre-workout meal (eaten 2–4 hours before exercise) should contain moderate protein (20–40 g), complex carbohydrates for sustained energy, and low-to-moderate fat. Example: chicken breast with rice and vegetables.

Question 20 Sports Nutrition

What is the 2:1 glucose-to-fructose ratio?

Yes. Creatine monohydrate is one of the most studied and safest supplements available. Research spanning decades shows no adverse effects on kidney or liver function in healthy individuals at recommended doses. Glutamine is the most abundant amino acid in the body, important for immune function and gut health. Intense exercise depletes glutamine levels. Supplementation (5–10 g/day) may support immune function in heavily training athletes, but evidence for muscle-building benefits is weak. This is largely a myth. Meal frequency has minimal impact on metabolic rate when total calorie and protein intake are equated. The thermic effect of food is determined by total intake, not meal frequency. Eating 3–6 meals per day based on preference and schedule is fine. Using a 2:1 ratio of glucose to fructose allows absorption of up to ~90 g carbs/hour by utilizing two different intestinal transport pathways (SGLT1 for glucose, GLUT5 for fructose), compared to ~60 g/hour from glucose alone.

Question 21 Sports Nutrition

What is the primary role of carbohydrates in sports performance?

Potassium helps regulate fluid balance, muscle contractions, and nerve signals. It works with sodium to maintain cellular hydration. Deficiency can cause muscle cramps and weakness. Athletes need 3500–4700 mg/day from foods like bananas, potatoes, spinach, and avocados. A calorie (technically kilocalorie, kcal) is a unit of energy. It represents the energy needed to raise the temperature of 1 kg of water by 1°C. In nutrition, it measures the energy content of foods and the energy expenditure of activities. Beginners can build muscle in a deficit (body recomposition). Intermediate athletes need a slight surplus for muscle gain. Advanced athletes need precise nutrition with small surpluses. Training status also affects glycogen utilization efficiency and fat oxidation capacity. Carbohydrates are the body's preferred fuel source during moderate-to-high intensity exercise. They are stored as glycogen in muscles and liver, providing readily available energy for athletic performance.

Question 22 Sports Nutrition

What is metabolic adaptation (adaptive thermogenesis)?

Metabolic adaptation is the body's reduction in energy expenditure beyond what is predicted by weight loss. It includes decreased BMR, reduced NEAT (non-exercise activity), improved movement efficiency, and hormonal changes (lower leptin, thyroid). It makes continued fat loss progressively harder. Plant proteins can be equally effective if consumed in sufficient quantity and variety to provide all essential amino acids. Plant proteins are generally lower in leucine and may have lower digestibility (DIAAS). Combining sources (e.g., rice + pea protein) creates a complete amino acid profile. High-GI foods are best consumed during and immediately after exercise when rapid glycogen replenishment and quick energy are beneficial. Examples include white bread, sports drinks, white rice, and ripe bananas. Diet breaks are planned periods (1–2 weeks) of eating at maintenance calories during a fat loss phase. Refeeds are shorter (1–2 days) periods of increased carbohydrate intake. Both may help counteract metabolic adaptation, reduce psychological stress, and restore leptin levels.

Question 23 Sports Nutrition

How much water should an athlete drink daily?

A calorie (technically kilocalorie, kcal) is a unit of energy. It represents the energy needed to raise the temperature of 1 kg of water by 1°C. In nutrition, it measures the energy content of foods and the energy expenditure of activities. Most sports nutrition guidelines recommend 1.2–2.0 g of protein per kg of body weight per day for athletes, depending on the sport and training intensity. Endurance athletes need ~1.2–1.4 g/kg; strength athletes need ~1.6–2.0 g/kg. General guideline: at least 3–4 liters per day for active individuals. A more precise method: drink enough to maintain pale yellow urine. During exercise, aim for 400–800 mL/hour depending on sweat rate and conditions. Saturated fats have no double bonds between carbon atoms (solid at room temperature, e.g., butter). Unsaturated fats have one or more double bonds (liquid at room temperature, e.g., olive oil). Unsaturated fats are generally considered healthier.

Question 24 Sports Nutrition

What is the role of leucine in muscle protein synthesis?

TEE is the energy expended during physical activity, including both structured exercise and non-exercise activity thermogenesis (NEAT). It is the most variable component of daily energy expenditure, ranging from 15–30% of TDEE depending on activity level. Sleep is critical because growth hormone is primarily released during deep sleep, facilitating muscle repair. Poor sleep increases cortisol, impairs glycogen replenishment, and increases appetite. A casein protein shake before bed can provide sustained amino acids during sleep. A pre-workout meal (eaten 2–4 hours before exercise) should contain moderate protein (20–40 g), complex carbohydrates for sustained energy, and low-to-moderate fat. Example: chicken breast with rice and vegetables. Leucine is the primary amino acid trigger for the mTOR signaling pathway, which activates muscle protein synthesis. A threshold of approximately 2.5–3 g of leucine per meal is needed to maximally stimulate this response.

Question 25 Sports Nutrition

What is the role of insulin in nutrient partitioning?

Insulin is an anabolic hormone released in response to carbohydrate and protein intake. It promotes glucose uptake into muscle cells, stimulates glycogen synthesis, enhances amino acid uptake, and inhibits protein breakdown. Post-exercise, it helps shuttle nutrients to recovering muscles. Citrulline malate increases nitric oxide production and arginine levels, improving blood flow and reducing fatigue. It may enhance endurance performance and reduce muscle soreness. Typical dose: 6–8 g taken 30–60 minutes pre-exercise. Weight loss includes loss of fat, muscle, water, and glycogen. Fat loss specifically targets adipose tissue. To maximize fat loss while preserving muscle: maintain a moderate deficit, keep protein high (2.0+ g/kg), perform resistance training, and lose 0.5–1% body weight per week. Iron is essential for hemoglobin (oxygen transport in blood) and myoglobin (oxygen storage in muscle). Iron deficiency impairs endurance performance, causes fatigue, and is common in female athletes and endurance athletes. RDA: 8 mg (males), 18 mg (females).

Question 26 Sports Nutrition

What is the glycemic index (GI)?

TEF is the energy required to digest, absorb, and process nutrients. Protein has the highest TEF (~20–30% of calories consumed), followed by carbohydrates (~5–10%) and fat (~0–3%). TEF accounts for ~10% of total daily energy expenditure. First determine calorie needs (TDEE). Then set protein (1.6–2.2 g/kg), fat (20–35% of calories), and fill remaining calories with carbohydrates. Example for 80 kg athlete at 3000 kcal: protein 160 g (640 kcal), fat 83 g (750 kcal), carbs 403 g (1610 kcal). Athletes should consume 20–35% of total daily calories from fat. Intake below 20% can impair hormone production and fat-soluble vitamin absorption. Emphasis should be on unsaturated fats. The glycemic index ranks carbohydrates on a scale of 0–100 based on how quickly they raise blood glucose. High GI foods (>70) cause rapid spikes; low GI foods (<55) produce slower, sustained rises. Medium GI is 56–69.

Question 27 Sports Nutrition

How should runners fuel for a marathon?

Marathon nutrition involves: carb loading (8–12 g/kg) for 2–3 days pre-race, a familiar pre-race meal 3–4 hours before, consuming 30–60 g carbs/hour during the race via gels/drinks, and aggressive post-race recovery with protein + carbs + electrolytes. The anabolic window is the supposed 30–60 minute post-exercise period when nutrient uptake is enhanced. Current research suggests this window is wider than originally thought (several hours), and total daily protein intake matters more than precise timing. Potassium helps regulate fluid balance, muscle contractions, and nerve signals. It works with sodium to maintain cellular hydration. Deficiency can cause muscle cramps and weakness. Athletes need 3500–4700 mg/day from foods like bananas, potatoes, spinach, and avocados. Branched-Chain Amino Acids (leucine, isoleucine, valine) make up ~35% of muscle protein. Leucine is the key trigger for muscle protein synthesis (mTOR pathway). BCAAs may reduce exercise-induced muscle damage and perceived fatigue.

Question 28 Sports Nutrition

What is the thermic effect of exercise (TEE)?

TEE is the energy expended during physical activity, including both structured exercise and non-exercise activity thermogenesis (NEAT). It is the most variable component of daily energy expenditure, ranging from 15–30% of TDEE depending on activity level. High-GI foods are best consumed during and immediately after exercise when rapid glycogen replenishment and quick energy are beneficial. Examples include white bread, sports drinks, white rice, and ripe bananas. The Female Athlete Triad consists of three interrelated conditions: low energy availability (with or without disordered eating), menstrual dysfunction (amenorrhea), and low bone mineral density (osteoporosis). It is now part of the broader concept of Relative Energy Deficiency in Sport (RED-S). A caloric surplus means consuming more calories than you expend. It is used for muscle gain (bulking). A moderate surplus of 250–500 kcal/day above TDEE promotes muscle growth while minimizing fat gain.

Question 29 Sports Nutrition

How does training status affect nutrition needs?

Yes. Creatine monohydrate is one of the most studied and safest supplements available. Research spanning decades shows no adverse effects on kidney or liver function in healthy individuals at recommended doses. Beginners can build muscle in a deficit (body recomposition). Intermediate athletes need a slight surplus for muscle gain. Advanced athletes need precise nutrition with small surpluses. Training status also affects glycogen utilization efficiency and fat oxidation capacity. Carbohydrates are the body's preferred fuel source during moderate-to-high intensity exercise. They are stored as glycogen in muscles and liver, providing readily available energy for athletic performance. Essential amino acids (EAAs) cannot be synthesized by the body and must come from diet (9 total). Non-essential amino acids can be produced by the body. Conditionally essential amino acids (e.g., glutamine) become essential during illness or stress.

Question 30 Sports Nutrition

What is the role of dietary fat in athletic performance?

Dietary fat provides essential fatty acids, supports hormone production (including testosterone), aids absorption of fat-soluble vitamins (A, D, E, K), and serves as a fuel source during low-intensity and prolonged exercise. Sodium is the primary electrolyte lost in sweat (average 500–1500 mg/L). It regulates fluid balance, nerve impulses, and muscle contractions. Athletes exercising >1 hour, especially in heat, should replace sodium to prevent hyponatremia and maintain performance. Athletes should consume 20–35% of total daily calories from fat. Intake below 20% can impair hormone production and fat-soluble vitamin absorption. Emphasis should be on unsaturated fats. Omega-3s (EPA and DHA) are essential polyunsaturated fatty acids found in fatty fish, flaxseed, and walnuts. They reduce inflammation, support cardiovascular health, may improve recovery, and have been linked to reduced exercise-induced muscle soreness.

Question 31 Sports Nutrition

What is glycogen supercompensation?

A complete protein contains all nine essential amino acids in adequate amounts: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Examples include meat, fish, eggs, dairy, soy, and quinoa. Research suggests 20–40 g of high-quality protein per meal maximally stimulates muscle protein synthesis. The leucine threshold of ~2.5–3 g per meal is key. Larger individuals and older adults may benefit from the higher end of this range. Glycogen supercompensation is the process of loading muscles with more glycogen than normal (up to 150–200% of resting levels) through a combination of glycogen-depleting exercise followed by high-carbohydrate intake (8–12 g/kg/day) for 1–3 days. Team sports require 5–7 g carbs/kg/day, 1.4–1.7 g protein/kg/day, with emphasis on pre-game carb loading and halftime refueling. Hydration is critical as games involve intermittent high-intensity efforts. Post-game recovery should focus on protein + carbs within 2 hours.

Question 32 Sports Nutrition

What is the role of probiotics in sports nutrition?

Simple carbs (monosaccharides, disaccharides) are quickly digested and raise blood sugar rapidly (e.g., fruit, sugar, honey). Complex carbs (polysaccharides) digest more slowly and provide sustained energy (e.g., oats, rice, potatoes). Probiotics are beneficial bacteria that support gut health and immune function. For athletes, they may reduce upper respiratory tract infections, improve GI symptoms during exercise, and support nutrient absorption. Strains like Lactobacillus and Bifidobacterium are most studied. Team sports require 5–7 g carbs/kg/day, 1.4–1.7 g protein/kg/day, with emphasis on pre-game carb loading and halftime refueling. Hydration is critical as games involve intermittent high-intensity efforts. Post-game recovery should focus on protein + carbs within 2 hours. Top sources include chicken breast, lean beef, fish (salmon, tuna), eggs, Greek yogurt, cottage cheese, whey protein, and plant sources like tofu, tempeh, and lentils. Quality is determined by amino acid profile and digestibility (DIAAS score).

Question 33 Sports Nutrition

What is a calorie?

This is largely a myth. Meal frequency has minimal impact on metabolic rate when total calorie and protein intake are equated. The thermic effect of food is determined by total intake, not meal frequency. Eating 3–6 meals per day based on preference and schedule is fine. Biological value measures the proportion of absorbed protein that is retained and used by the body. Whole egg has a BV of 100 (reference), whey protein ~104, casein ~77, and soy ~74. A calorie (technically kilocalorie, kcal) is a unit of energy. It represents the energy needed to raise the temperature of 1 kg of water by 1°C. In nutrition, it measures the energy content of foods and the energy expenditure of activities. The glycemic index ranks carbohydrates on a scale of 0–100 based on how quickly they raise blood glucose. High GI foods (>70) cause rapid spikes; low GI foods (<55) produce slower, sustained rises. Medium GI is 56–69.

Question 34 Sports Nutrition

What are medium-chain triglycerides (MCTs)?

MCTs are fats with 6–12 carbon chains that are rapidly absorbed and transported directly to the liver for oxidation. They provide quick energy but their ergogenic benefit is limited and may cause GI distress at effective doses. Found in coconut oil. Dietary fat provides essential fatty acids, supports hormone production (including testosterone), aids absorption of fat-soluble vitamins (A, D, E, K), and serves as a fuel source during low-intensity and prolonged exercise. Insulin is an anabolic hormone released in response to carbohydrate and protein intake. It promotes glucose uptake into muscle cells, stimulates glycogen synthesis, enhances amino acid uptake, and inhibits protein breakdown. Post-exercise, it helps shuttle nutrients to recovering muscles. Biological value measures the proportion of absorbed protein that is retained and used by the body. Whole egg has a BV of 100 (reference), whey protein ~104, casein ~77, and soy ~74.

Question 35 Sports Nutrition

What is the recommended creatine dosage?

Periodized nutrition involves adjusting calorie and macronutrient intake based on training phase. During high-volume training: more carbs. During strength phases: more protein. During off-season: moderate intake. This optimizes performance, body composition, and recovery throughout the training year. Athletes should consume 20–35% of total daily calories from fat. Intake below 20% can impair hormone production and fat-soluble vitamin absorption. Emphasis should be on unsaturated fats. The standard protocol is a loading phase of 20 g/day (split into 4 doses) for 5–7 days, followed by a maintenance dose of 3–5 g/day. Alternatively, taking 3–5 g/day without loading saturates muscles in ~28 days. Most sports nutrition guidelines recommend 1.2–2.0 g of protein per kg of body weight per day for athletes, depending on the sport and training intensity. Endurance athletes need ~1.2–1.4 g/kg; strength athletes need ~1.6–2.0 g/kg.

Question 36 Sports Nutrition

When should high-GI foods be consumed by athletes?

No. Supplements are not required for muscle building. A well-planned diet can provide all necessary nutrients. However, creatine, protein powder, and vitamin D may be convenient and beneficial when dietary intake is insufficient. Supplements should supplement, not replace, real food. TDEE = BMR × Activity Factor. BMR (Basal Metabolic Rate) can be estimated using equations like Mifflin-St Jeor. Activity factors: sedentary (1.2), light (1.375), moderate (1.55), active (1.725), very active (1.9). High-GI foods are best consumed during and immediately after exercise when rapid glycogen replenishment and quick energy are beneficial. Examples include white bread, sports drinks, white rice, and ripe bananas. Top sources include chicken breast, lean beef, fish (salmon, tuna), eggs, Greek yogurt, cottage cheese, whey protein, and plant sources like tofu, tempeh, and lentils. Quality is determined by amino acid profile and digestibility (DIAAS score).

Question 37 Sports Nutrition

What is whey protein?

Whey protein is a fast-digesting, complete protein derived from milk during cheese production. It is rich in BCAAs (especially leucine) and has a high biological value. Types include concentrate (~80% protein), isolate (~90%), and hydrolysate (pre-digested). The standard protocol is a loading phase of 20 g/day (split into 4 doses) for 5–7 days, followed by a maintenance dose of 3–5 g/day. Alternatively, taking 3–5 g/day without loading saturates muscles in ~28 days. B vitamins are coenzymes in energy metabolism. B1 (thiamine), B2 (riboflavin), and B3 (niacin) are involved in energy production. B6 aids protein metabolism. B12 and folate support red blood cell production. Athletes with restricted diets may need supplementation. Marathon nutrition involves: carb loading (8–12 g/kg) for 2–3 days pre-race, a familiar pre-race meal 3–4 hours before, consuming 30–60 g carbs/hour during the race via gels/drinks, and aggressive post-race recovery with protein + carbs + electrolytes.

Question 38 Sports Nutrition

How does fiber affect athletic performance?

Fiber supports gut health, blood sugar regulation, and satiety. However, high-fiber foods should be avoided 2–3 hours before exercise as they can cause GI discomfort. Athletes should aim for 25–35 g/day, timed away from training. Simple carbs (monosaccharides, disaccharides) are quickly digested and raise blood sugar rapidly (e.g., fruit, sugar, honey). Complex carbs (polysaccharides) digest more slowly and provide sustained energy (e.g., oats, rice, potatoes). During exercise lasting >60 minutes, consume 30–60 g of carbohydrates per hour from easily digestible sources (sports drinks, gels, bananas). For events >2.5 hours, intake can be increased to up to 90 g/hour using glucose + fructose combinations. A caloric deficit means consuming fewer calories than you expend. It is necessary for fat loss. A moderate deficit of 300–500 kcal/day below TDEE promotes fat loss while preserving muscle mass (with adequate protein and resistance training).

Question 39 Sports Nutrition

What is the best nutrition for swimming?

Concentrate: 70–80% protein, contains some fat and lactose. Isolate: 90%+ protein, minimal fat/lactose, faster absorption. Hydrolysate: pre-digested for fastest absorption, most expensive. All are effective; isolate is best for lactose-intolerant individuals. Swimmers need high carbohydrate intake (6–10 g/kg/day) due to high training volumes. Pool chlorine increases oxidative stress, so antioxidant-rich foods are beneficial. Meals should be timed 2–3 hours before training. Recovery nutrition is critical due to multiple daily sessions. Omega-3s (EPA and DHA) are essential polyunsaturated fatty acids found in fatty fish, flaxseed, and walnuts. They reduce inflammation, support cardiovascular health, may improve recovery, and have been linked to reduced exercise-induced muscle soreness. Citrulline malate increases nitric oxide production and arginine levels, improving blood flow and reducing fatigue. It may enhance endurance performance and reduce muscle soreness. Typical dose: 6–8 g taken 30–60 minutes pre-exercise.

Question 40 Sports Nutrition

What is the Mifflin-St Jeor equation?

Magnesium is involved in 300+ enzymatic reactions including energy production, muscle contraction, protein synthesis, and nerve function. Deficiency can cause cramps, fatigue, and impaired performance. Athletes may need 400–600 mg/day. Found in nuts, seeds, leafy greens. Gut training involves practicing race-day nutrition during training to improve gastrointestinal tolerance and nutrient absorption. The gut can be trained to absorb more carbohydrate (up to 90 g/hour) and tolerate foods during exercise with consistent practice. For males: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 5. For females: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161. It is considered the most accurate BMR prediction equation. This is largely a myth. Meal frequency has minimal impact on metabolic rate when total calorie and protein intake are equated. The thermic effect of food is determined by total intake, not meal frequency. Eating 3–6 meals per day based on preference and schedule is fine.

Question 41 Sports Nutrition

What are the nutritional needs of masters athletes (over 40)?

First determine calorie needs (TDEE). Then set protein (1.6–2.2 g/kg), fat (20–35% of calories), and fill remaining calories with carbohydrates. Example for 80 kg athlete at 3000 kcal: protein 160 g (640 kcal), fat 83 g (750 kcal), carbs 403 g (1610 kcal). The anabolic window is the supposed 30–60 minute post-exercise period when nutrient uptake is enhanced. Current research suggests this window is wider than originally thought (several hours), and total daily protein intake matters more than precise timing. RED-S describes impaired physiological function caused by low energy availability, affecting both males and females. It impacts metabolism, menstrual function, bone health, immunity, protein synthesis, cardiovascular health, and psychological well-being. Masters athletes need higher protein (1.6–2.2 g/kg/day) due to anabolic resistance, adequate vitamin D and calcium for bone health, omega-3s for inflammation management, and may benefit from creatine supplementation. Recovery takes longer, so post-workout nutrition timing is more important.

Question 42 Sports Nutrition

What is citrulline malate?

Weight loss includes loss of fat, muscle, water, and glycogen. Fat loss specifically targets adipose tissue. To maximize fat loss while preserving muscle: maintain a moderate deficit, keep protein high (2.0+ g/kg), perform resistance training, and lose 0.5–1% body weight per week. Citrulline malate increases nitric oxide production and arginine levels, improving blood flow and reducing fatigue. It may enhance endurance performance and reduce muscle soreness. Typical dose: 6–8 g taken 30–60 minutes pre-exercise. Concentrate: 70–80% protein, contains some fat and lactose. Isolate: 90%+ protein, minimal fat/lactose, faster absorption. Hydrolysate: pre-digested for fastest absorption, most expensive. All are effective; isolate is best for lactose-intolerant individuals. A caloric surplus means consuming more calories than you expend. It is used for muscle gain (bulking). A moderate surplus of 250–500 kcal/day above TDEE promotes muscle growth while minimizing fat gain.

Question 43 Sports Nutrition

What is the Female Athlete Triad?

Antioxidants (vitamins C, E, selenium, polyphenols) neutralize free radicals produced during exercise. However, excessive supplementation may blunt training adaptations, as some oxidative stress is needed for adaptation signaling. Whole foods are preferred over supplements. Team sports require 5–7 g carbs/kg/day, 1.4–1.7 g protein/kg/day, with emphasis on pre-game carb loading and halftime refueling. Hydration is critical as games involve intermittent high-intensity efforts. Post-game recovery should focus on protein + carbs within 2 hours. A pre-workout meal (eaten 2–4 hours before exercise) should contain moderate protein (20–40 g), complex carbohydrates for sustained energy, and low-to-moderate fat. Example: chicken breast with rice and vegetables. The Female Athlete Triad consists of three interrelated conditions: low energy availability (with or without disordered eating), menstrual dysfunction (amenorrhea), and low bone mineral density (osteoporosis). It is now part of the broader concept of Relative Energy Deficiency in Sport (RED-S).

Question 44 Sports Nutrition

What should a post-workout meal contain?

Zinc supports immune function, protein synthesis, testosterone production, and wound healing. Exercise increases zinc loss through sweat and urine. RDA: 11 mg (males), 8 mg (females). Found in meat, shellfish, legumes, and seeds. Carbohydrates are the body's preferred fuel source during moderate-to-high intensity exercise. They are stored as glycogen in muscles and liver, providing readily available energy for athletic performance. Biological value measures the proportion of absorbed protein that is retained and used by the body. Whole egg has a BV of 100 (reference), whey protein ~104, casein ~77, and soy ~74. A post-workout meal should include protein (20–40 g) to stimulate muscle protein synthesis and carbohydrates (0.8–1.2 g/kg) to replenish glycogen stores. Consuming this within 2 hours post-exercise is generally recommended.

Question 45 Sports Nutrition

What should a pre-workout meal contain?

Simple carbs (monosaccharides, disaccharides) are quickly digested and raise blood sugar rapidly (e.g., fruit, sugar, honey). Complex carbs (polysaccharides) digest more slowly and provide sustained energy (e.g., oats, rice, potatoes). RED-S describes impaired physiological function caused by low energy availability, affecting both males and females. It impacts metabolism, menstrual function, bone health, immunity, protein synthesis, cardiovascular health, and psychological well-being. Essential amino acids (EAAs) cannot be synthesized by the body and must come from diet (9 total). Non-essential amino acids can be produced by the body. Conditionally essential amino acids (e.g., glutamine) become essential during illness or stress. A pre-workout meal (eaten 2–4 hours before exercise) should contain moderate protein (20–40 g), complex carbohydrates for sustained energy, and low-to-moderate fat. Example: chicken breast with rice and vegetables.

Question 46 Sports Nutrition

What should athletes eat for breakfast?

Masters athletes need higher protein (1.6–2.2 g/kg/day) due to anabolic resistance, adequate vitamin D and calcium for bone health, omega-3s for inflammation management, and may benefit from creatine supplementation. Recovery takes longer, so post-workout nutrition timing is more important. A caloric surplus means consuming more calories than you expend. It is used for muscle gain (bulking). A moderate surplus of 250–500 kcal/day above TDEE promotes muscle growth while minimizing fat gain. Glycogen is the stored form of glucose found in muscles (~300–400 g) and the liver (~75–100 g). It is the primary fuel for exercise above ~65% VO2max and its depletion leads to fatigue and reduced performance. An ideal athletic breakfast includes protein (eggs, Greek yogurt, protein shake), complex carbs (oats, whole grain toast), and healthy fats (nuts, avocado). Example: 3-egg omelet with vegetables, oatmeal with berries, and a glass of milk (~600–800 kcal, 40 g protein).

Question 47 Sports Nutrition

What is the importance of sodium for athletes?

High-GI foods are best consumed during and immediately after exercise when rapid glycogen replenishment and quick energy are beneficial. Examples include white bread, sports drinks, white rice, and ripe bananas. Sodium is the primary electrolyte lost in sweat (average 500–1500 mg/L). It regulates fluid balance, nerve impulses, and muscle contractions. Athletes exercising >1 hour, especially in heat, should replace sodium to prevent hyponatremia and maintain performance. TEE is the energy expended during physical activity, including both structured exercise and non-exercise activity thermogenesis (NEAT). It is the most variable component of daily energy expenditure, ranging from 15–30% of TDEE depending on activity level. First determine calorie needs (TDEE). Then set protein (1.6–2.2 g/kg), fat (20–35% of calories), and fill remaining calories with carbohydrates. Example for 80 kg athlete at 3000 kcal: protein 160 g (640 kcal), fat 83 g (750 kcal), carbs 403 g (1610 kcal).

Question 48 Sports Nutrition

What is the thermic effect of food (TEF)?

Athletes should consume 20–35% of total daily calories from fat. Intake below 20% can impair hormone production and fat-soluble vitamin absorption. Emphasis should be on unsaturated fats. TEF is the energy required to digest, absorb, and process nutrients. Protein has the highest TEF (~20–30% of calories consumed), followed by carbohydrates (~5–10%) and fat (~0–3%). TEF accounts for ~10% of total daily energy expenditure. TEE is the energy expended during physical activity, including both structured exercise and non-exercise activity thermogenesis (NEAT). It is the most variable component of daily energy expenditure, ranging from 15–30% of TDEE depending on activity level. HMB is a metabolite of leucine that may reduce muscle protein breakdown and support recovery. It appears most effective for untrained individuals or during caloric restriction. Typical dose: 3 g/day divided into 3 doses. Benefits for trained athletes are less clear.

Question 49 Sports Nutrition

What are sports drinks and when should they be used?

Sports drinks contain water, carbohydrates (6–8%), and electrolytes. They are beneficial during exercise lasting >60 minutes or in hot conditions. For exercise <60 minutes, water is usually sufficient. Examples: isotonic drinks match blood osmolality for optimal absorption. For males: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 5. For females: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161. It is considered the most accurate BMR prediction equation. Probiotics are beneficial bacteria that support gut health and immune function. For athletes, they may reduce upper respiratory tract infections, improve GI symptoms during exercise, and support nutrient absorption. Strains like Lactobacillus and Bifidobacterium are most studied. Electrolytes are minerals that carry an electrical charge: sodium, potassium, chloride, calcium, magnesium. They regulate fluid balance, nerve function, and muscle contraction. Athletes lose them through sweat, especially sodium (500–1500 mg/L of sweat).

Question 50 Sports Nutrition

What is hyponatremia?

Hyponatremia is dangerously low blood sodium levels (<135 mmol/L), often caused by drinking excessive water without adequate sodium replacement during prolonged exercise. Symptoms include nausea, confusion, seizures; can be fatal. Antioxidants (vitamins C, E, selenium, polyphenols) neutralize free radicals produced during exercise. However, excessive supplementation may blunt training adaptations, as some oxidative stress is needed for adaptation signaling. Whole foods are preferred over supplements. Probiotics are beneficial bacteria that support gut health and immune function. For athletes, they may reduce upper respiratory tract infections, improve GI symptoms during exercise, and support nutrient absorption. Strains like Lactobacillus and Bifidobacterium are most studied. Beginners can build muscle in a deficit (body recomposition). Intermediate athletes need a slight surplus for muscle gain. Advanced athletes need precise nutrition with small surpluses. Training status also affects glycogen utilization efficiency and fat oxidation capacity.