Impact of Sleep, Nutrition, and Supplementation on Movement and Performance Notes

Dietary Requirements for Athletes and Energy Availability

• For athletes to move and perform at peak effectiveness, their body must be in good condition, primarily maintained through nutrition and sleep.

• Dietary and fluid intake requirements are based on the intensity, duration, and type of activity.

• The Australian Institute of Sport (AIS) Performance Nutrition HQ provides e-learning modules covering:

  • Nutrition Fundamentals

  • Training and Competition Nutrition

  • Hydration

  • Building Your Nutrition Plan

  • Supplements

  • Understanding Food Labels

• Pre-performance nutrition focuses on balancing carbohydrates, proteins, and fats for sustained energy and endurance.

• During performance, the focus is on maintaining hydration and replenishing electrolytes to prevent dehydration.

• Post-performance nutrition shifts to recovery, specifically using proteins and carbohydrates to repair muscle tissues and restore glycogen levels.

• Factors that make refueling challenging include:

  • Stomach discomfort or unwanted toilet breaks during sessions.

  • Difficulty meeting body composition goals.

  • Hunger issues during performance.

  • Limited storage capacity for glycogen in skeletal muscles and the liver.

Pre-Performance Nutrition and Carbohydrate Loading

• The objective of a training diet is to achieve nutritional adequacy (vitamins and minerals) and provide appropriate energy for training and body composition goals.

• Nutritional targets should be based on an individual's goal body weight and muscle mass.

• Carbohydrates (starches and sugars) are the key fuel source for high-intensity and prolonged exercise. Inadequate intake lead to fatigue, poor concentration, reduced immune function, and increased injury risk.

• Carbohydrate requirements based on exercise intensity:

  • Light-intensity ($30\,\text{min/day}$): $3-5\,\text{g/kg/day}$.

  • Moderate-intensity ($60\,\text{min/day}$): $5-7\,\text{g/kg/day}$.

  • Endurance exercise ($1-3\,\text{hrs/day}$): $6-10\,\text{g/kg/day}$.

  • Extreme endurance (>4\,\text{hrs/day}): $8-12\,\text{g/kg/day}$.

• Carbohydrate loading aims to maximize muscle glycogen stores. It is beneficial for endurance events lasting over $90\,\text{minutes}$ (marathons, triathlons, road race cycling), where it can improve performance by $2-3\%$.

• Loading Protocols:

  • Traditional: 3-4 day depletion phase (hard training/low carb) followed by 3-4 day loading phase (tapered training/high carb).

  • Modern: High-carbohydrate diet ($8-12\,\text{g/kg}$ body weight) for $36-48\,\text{hours}$ while rested.

• Effective loading typically results in weight gain of approximately $1\,\text{kg}$ due to stored glycogen and the water stored with it; this is not an increase in body fat.

• Pre-event meal goals:

  • Fuel and hydrate the body.

  • Maximize training quality and quantity.

  • Avoid stomach discomfort and hunger.

• Characteristics of the pre-event meal:

  • High in carbohydrates, moderate in protein.

  • Low in fiber and fat (fat slows digestion).

  • Familiar (no experimentation on event day).

• Timing of pre-event intake:

  • $3-4\,\text{hours}$ before: Crumpets with jam, pancakes with honey, baked beans on toast, pasta with tomato-based sauce.

  • $1-2\,\text{hours}$ before: Milkshakes, fruit smoothies, fruit-flavored yogurt, low-fiber cereal with milk, or fruit.

• Liver glycogen and sleep: The brain remains active during sleep and uses liver glycogen. Athletes with early morning starts must eat extra early or have a high-carb snack $1-2\,\text{hours}$ before starting to top up liver glycogen losses from the overnight fast.

Nutrition and Hydration During and After Performance

• During performance, the need for carbohydrate intake depends on duration:

  • <60-90\,\text{minutes}: Typically no extra carbohydrate needed; small fluid amounts based on sweat.

  • >90\,\text{minutes}: Benefit from topping up fuel stores; fluid based on sweat rate.

  • >4\,\text{hours}: Unique, intensive fueling and hydration needs.

  • Gala days/tournaments: Important to consume carbohydrates between sessions as glycogen depletes over the day.

• Combination of "sports foods" (gels, drinks) and "real foods" (fruit, low-fiber sandwiches) is often best tolerated to avoid bloating or diarrhea. These also provide electrolytes (sodium, potassium, magnesium).

• Post-performance recovery aims to refuel glycogen, repair muscle tissue, boost adaptation, and support immune function (which can be suppressed for hours after high-intensity exercise).

• Recovery timing and intake:

  • Optimal window: Refueling activity is highest in the first $60-90\,\text{minutes}$.

  • Carbohydrate target: $1-1.2\,\text{g/kg}$ body weight within the first hour, specifically using high-glycaemic index (GI), low-fiber foods.

  • Protein target: Approximately $15\,\text{g}$ for general high-intensity recovery. For strength/power athletes, research suggests $300\,\text{mg/kg}$ of ideal body weight (roughly $21\,\text{g}$ for a $70\,\text{kg}$ athlete).

• Recovery meal examples: Chocolate milk, yogurt with fruit salad, chicken and salad roll, or a burrito.

Hydration Strategies and Sweat Monitoring

• Pre-event hydration: $300-600\,\text{mL}$ with the pre-event meal, plus $300-400\,\text{mL}$ approximately $20\,\text{minutes}$ before the event.

• Performance decline occurs at just $2\%$ dehydration. Effects include:

  • Reduced mental function/concentration.

  • Increased perceived exertion (fatigue at lower intensity).

  • Delayed gastric emptying (stomach discomfort).

  • Poor aerobic performance and impaired heat regulation.

• Calculating sweat rate: $1\,\text{kg}$ weight loss during exercise equals approximately $1\,\text{L}$ of fluid loss.

• Hyponatraemia: Abnormally low blood sodium levels caused by over-hydrating with low-sodium fluids (like water) when sweat losses are small.

  • Symptoms are similar to dehydration and can be life-threatening.

  • Small females with long race times (>3-4\,\text{hours}) are at highest risk.

  • Prevention: Consume sodium-containing fluids (sports drinks) or foods (vegemite sandwiches).

• Monitoring hydration:

  • Urine color chart: Levels 1-2 (Hydrated), 3-4 (Slightly dehydrated), 5-6 (Dehydrated), 7-8 (Very dehydrated).

  • Urine specific gravity tests.

• Daily hydration guidelines (Australia): Men ($2500\,\text{mL}$ or 10 glasses); Women ($2000\,\text{mL}$ or 8 glasses).

Sleep Fundamentals and the QQRT Protocol

• Sleep is essential for muscle coordination, faster reaction times, and balance/stability.

• Restoration processes during sleep: Muscle repair, protein synthesis, and release of growth hormones.

• QQRT Elements:

  • Quantity: Adults typically need $7-9\,\text{hours}$ per night.

  • Quality: Depth and continuity; frequent awakenings indicate poor quality.

  • Regularity: Consistent sleep and wake times (within a $30\,\text{minute}$ window).

  • Timing: Aligning sleep with an individual's chronotype.

• Sleep Monitoring Tools:

  • Trackers: Devices measuring duration, quality, stages (light, deep, REM), heart rate, and blood oxygen.

  • Polysomnography (Medical Sleep Study): Comprehensive test monitoring brain waves (EEG), eye movements (EOG), muscle activity (EMG), and heart rate (ECG).

• Routines for better sleep: Dim lights, limit screen time, early caffeine intake, cool bedroom, and a 10-minute morning outdoor exposure.

Supplementation and the AIS Framework

• AIS Supplement Groups:

  • Group A: Strong scientific evidence for use (sports foods like drinks/gels; medical supplements like iron; performance supplements like caffeine/creatine).

  • Group B: Emerging evidence; considered for research or clinical monitoring (polyphenols, antioxidants, tastants like pickle juice).

  • Group C: Insufficient evidence of benefits (magnesium, prebiotics, phosphate).

  • Group D: Banned substances (stimulants, hormone boosters, peptides, SARMs).

• Micronutrients: Vitamins (fat-soluble A, D, E, K; water-soluble B and C) and Minerals.

  • Vitamin A: Vision and immune function.

  • Vitamin B1 (Thiamine): Carb-to-energy conversion.

  • Vitamin B12: Red blood cell formation.

  • Vitamin C: Antioxidant and collagen synthesis.

  • Vitamin D: Bone health and muscle function.

• Key Minerals for Athletes:

  • Calcium: Bone health and muscle contraction. Deficiency leads to osteopenia and osteoporosis.

  • Iron: Component of haemoglobin for oxygen transport. Low iron causes reduced energy production and sports anaemia (lethargy caused by increased training load/blood volume expansion).

  • Zinc: Protein synthesis and muscle repair.

Specific Ergogenic Aids: Protein, Caffeine, and Creatine

• Protein:

  • Recommended intake: $1.2-1.6\,\text{g/kg}$ body mass.

  • Types: Whey (fast-digesting, high leucine), Casein (slow-digesting, used before bed), Egg (dairy-free), Soy (plant-based complete protein), Pea (hypoallergenic).

  • Optimal methodology: Spread intake into $15-25\,\text{g}$ servings throughout the day rather than one large meal.

• Caffeine:

  • Primary effect: Central nervous system (CNS) arousal, reducing perception of fatigue/pain and improving pacing.

  • Dosage: Up to $3\,\text{mg/kg}$ body mass per day to minimize side effects.

  • Sources: Coffee, energy drinks, tea, cola, and pre-workout supplements.

• Creatine:

  • Function: Regenerates ATP for high-intensity efforts lasting up to $10\,\text{seconds}$.

  • Source: Naturally in animal muscle (meat/fish) at $1-2\,\text{g/day}$. Vegetarians typically have lower resting levels and see greater benefits from supplementation.

  • Loading protocols:

    • Rapid: $20\,\text{g}$ total per day (four $5\,\text{g}$ doses) for 5 days.

    • Slow: $3-5\,\text{g}$ daily for 28 days.

    • Maintenance: $0.03\,\text{g/kg}$ body mass per day.

  • Weight gain: Sharp increase of $600-1000\,\text{g}$ is expected due to water retention.

Questions & Discussion

• Case Study 8.1: Jemima Montag (Racewalker)

  • What challenges did Jemima mention regarding nutrition as a female athlete?

  • How did she organize nutrition for competition versus training?

  • Why did her plan include three weeks of high intensity followed by a "deload" week?

  • How can nutrition assist with the impact of the menstrual cycle on training?

• Driving Questions regarding dietary changes:

  • What specific dietary changes are made for increased activity and why?

  • What are the detriments to an elite athlete who regularly neglects their diet?

• Review Questions:

  • Compare the dietary requirements of a power athlete to an endurance athlete.

  • Explain the role of carbohydrates, proteins, and fats in physical performance.

  • Discuss the ethical considerations of marketing supplements to adolescents.

  • Evaluate the evidence for creatine in cognitive enhancement.