George Sports Dietitian

29/07/2025

📢Did you know?🎯

You can get better results when you align your training and nutrition with your menstrual cycle.🙌💪♥️

Your hormones fluctuate each week, affecting your energy levels, recovery, strength, and even how your body uses fuel. By adjusting your workouts and what you eat to match these changes, you can optimise performance, reduce fatigue, support recovery, and feel more in tune with your body.

Train smarter, not harder — sync with your cycle. 💪🩸

How to book an appointment:
lizedietitian@gmail.com
082 578 5092

Lize Esterhuysen is a registered Dietitian with a special interest in sports nutrition. She completed a sports nutrition course through the Association for Dietetics in South Africa (ADSA) and a triathlon nutrition course from Jeffrey Rothschild.

05/06/2025

Calcium's role in sport:

✅ Electrolyte Role:
-Calcium carries an electrical charge (Ca²⁺) and helps conduct electrical signals, especially in muscle contraction and nerve transmission.
-It’s essential for triggering muscle contractions, including both skeletal and cardiac muscle.

⚠️ Not a Major Player in Hydration:
-Calcium is not significantly lost through sweat compared to sodium or chloride.
-Therefore, it's not a focus in electrolyte drinks or acute hydration strategies.

🦴 Long-Term Importance:
-Athletes, especially women, need adequate dietary calcium for bone health, particularly if energy intake is low or there’s menstrual dysfunction (like RED-S).
-Low calcium combined with high training load increases risk of stress fractures and osteopenia.

🥛 Sources:
Best absorbed from dairy (e.g., milk, yogurt, cheese), but also found in leafy greens, almonds, and fortified foods.

🔄 Interaction with Other Electrolytes:
Calcium metabolism is influenced by vitamin D, and it interacts with magnesium and phosphorus. An imbalance can affect absorption and muscle performance.

Summary:
Calcium is an electrolyte, but its main relevance in sports nutrition is long-term (bone health, muscle function), not immediate hydration or cramp prevention. It's important in the background physiology of performance, rather than acute endurance fuelling.

29/05/2025

Role of Magnesium in Sports Nutrition:

💪Muscle Function: Magnesium plays a crucial role in muscle contraction and relaxation. Deficiency can lead to cramps, spasms, or muscle fatigue.

💃Energy Production: It's involved in over 300 enzymatic reactions, many of which are required to convert food into energy (ATP synthesis).

⚖️Electrolyte Balance: Although not a primary regulator like sodium or potassium, magnesium plays a crucial role in maintaining cellular electrolyte balance and supporting nerve signal transmission.

👌Lactic Acid Buffering: May help reduce the buildup of lactic acid during intense activity, possibly improving endurance and reducing muscle soreness.

♥️Heart Rhythm: Magnesium supports cardiac rhythm, especially important for endurance athletes.

Magnesium Loss Through Exercise:

🌻Intense sweating leads to minor but cumulative magnesium loss.
🌻Athletes training in hot/humid conditions or for long durations are at greater risk.
🌻Deficiency symptoms include fatigue, irritability, poor recovery, and irregular heartbeat.

Sources and Supplementation:

🥦Dietary: Leafy greens, whole grains, nuts (almonds, cashews), dairy, and dark chocolate.

Supplements: Often included in electrolyte tablets or powders. Common forms include magnesium citrate, glycinate, or oxide (though oxide is less bioavailable).

Dosage: Typical recommended daily intake is ~300–400 mg/day for adults. Athletes may require slightly more, but excess can cause GI distress (especially magnesium oxide).

In Practice:
🎉For most recreational athletes, a well-rounded diet can cover magnesium needs.

🎉Endurance athletes or those with high sweat losses may benefit from magnesium-rich meals or targeted supplements, especially during long training blocks or in the luteal phase of the menstrual cycle when requirements may rise

21/05/2025

📢Just completed another course in endurance sports nutrition, focusing on triathletes and considering the differences between male and female athletes.🎉

As a registered dietitian with a special interest in sports nutrition, it's essential to continually expand my knowledge and stay aligned with current, evidence-based research.🙌

Endurance athletes, especially triathletes, have unique and complex nutritional needs that evolve across training phases and race day. This course provided updated insights into fuelling strategies, hydration, recovery, and periodised nutrition, considering the menstrual cycle—all based on the latest science.

With so much conflicting information in the sports world, it's my priority to ensure that the guidance I provide is practical and also rooted in credible research. Supporting athletes with accurate, tailored nutrition is key to both performance and long-term health.

15/05/2025

🔋 Role of Chloride as an Electrolyte
Chloride (Cl⁻) is the major extracellular anion and works closely with sodium (Na⁺) and potassium (K⁺) to maintain fluid and electrolyte balance in the body. Its main functions include:

1. Maintaining Fluid Balance
-Helps regulate osmotic pressure and hydration by balancing water movement between body compartments.
-Works with sodium to maintain extracellular fluid volume.

2. Acid-Base Balance
-Key component of hydrochloric acid (HCl) in the stomach, essential for digestion.
-Plays a role in the bicarbonate buffer system, helping maintain blood pH (acid-base homeostasis).

3. Nerve Function and Muscle Contraction
-Chloride ions are involved in electrical neutrality and support nerve impulse transmission.
-Contribute to resting membrane potential, which is vital for muscle contractions.

🏃‍♂️ Importance in Sport Nutrition and Athletic Performance
Athletes have increased chloride requirements due to:

1. Losses in Sweat
Chloride is lost in significant amounts in sweat, especially during prolonged or intense exercise.

These losses must be replenished to prevent electrolyte imbalances, which can cause:
-Muscle cramps
-Fatigue
-Dehydration
-Poor thermoregulation

2. Hydration and Electrolyte Replenishment
-Sports drinks often contain sodium chloride to help restore electrolyte balance post-exercise.
-Maintaining chloride levels is essential for optimal rehydration, particularly in hot climates or long-duration events.

3. Supporting Performance and Recovery
-Proper chloride balance supports:
-Efficient nerve function and muscle responsiveness
-Stable blood pH during high-intensity exercise
-Digestive efficiency, promoting nutrient absorption

🥤 Practical Guidelines for Athletes
-Include electrolyte-rich fluids (e.g., sports drinks) during and after workouts.
-Be cautious of overhydration with plain water, which can dilute electrolytes (hyponatremia).
-Consume salt-containing foods (in moderation-) post-exercise to aid recovery.

17/04/2025

🧠 What Is Potassium?
Potassium is a mineral and electrolyte that helps maintain fluid balance, nerve function, and muscle contraction — all vital during physical activity.

🏃‍♂️ Key Roles of Potassium in Sports Nutrition
Muscle Function & Cramp Prevention
Potassium helps muscles contract properly.

Low levels can lead to muscle weakness, fatigue, or cramps

Nerve Signal Transmission
It works with sodium to send electrical signals between cells.

This is especially important for quick reflexes and proper muscle coordination.

Fluid & Electrolyte Balance
During exercise, you sweat and lose electrolytes.

Potassium helps regulate hydration and keeps cells from dehydrating, maintaining endurance and energy levels.

Acid-Base Balance
Potassium helps balance pH levels in the body, which can affect performance and recovery.

Supports Heart Function
Vital for maintaining a steady heartbeat during intense activity.

💧 Potassium Loss During Exercise
You lose potassium when you sweat, especially in hot environments or during long workouts.

Endurance athletes (e.g., marathoners, triathletes) are at higher risk of depletion.

🥗 Good Sources of Potassium in Diet
Bananas (classic sports snack)
Sweet potatoes
Avocados
Leafy greens (e.g., spinach)
Coconut water (popular natural electrolyte drink)
Yogurt
Beans

🧃 Potassium in Sports Drinks
Some sports drinks include potassium (along with sodium and sometimes magnesium) to replenish lost electrolytes and improve hydration during or after intense workouts.

✅ Daily Potassium Total: ~5,700–6,000 mg
(The recommended daily intake for adults is around 3,400 mg for men and 2,600 mg for women — athletes may benefit from more due to losses from sweat.)

16/04/2025

Low energy availability or underfueling can have serious side effects—especially if it’s not managed properly with guidance from a sports nutrition-focused dietitian.

Take a look at some common signs and symptoms to watch out for:

14/04/2025

🤣Runner humour🏃

10/04/2025

🧂Sodium is a crucial electrolyte during exercise for several key reasons:

⚖️Maintains Fluid Balance: Sodium helps regulate the amount of water in and around cells. When you sweat, you lose both water and sodium. Without enough sodium, your body can't retain the fluid it needs, leading to dehydration.

👌Supports Nerve Function: Sodium is essential for proper nerve signal transmission. During exercise, nerves need to rapidly communicate with muscles, and sodium helps generate the electrical impulses that make this possible.

💧Prevents Hyponatremia: If you drink a lot of plain water without replacing sodium, your blood sodium levels can drop too low, leading to a dangerous condition called hyponatremia. Symptoms include confusion, nausea, headaches, and in severe cases, seizures or death.

💪Aids Muscle Contraction: Sodium, along with potassium and calcium, helps muscles contract and relax properly. An imbalance can lead to cramps or poor performance.

In short, sodium keeps your body's systems running smoothly during exercise, especially in hot environments or during long-duration workouts.

27/03/2025

📢Why is it so important to pre-fuel, re-fuel and recover?🥪

Muscle glycogen becomes depleted at around 60-90min during intense exercise. When muscle glycogen is at full capacity, at most, the glycogen stores might last you around 90-120 minutes at around 65-75% of your maximal heart rate.♥️

If you’re training intensely most days for extended periods, it’s likely that your glycogen stores are not fully replenished and are slightly depleted.⬇️

The amount of glycogen you need depends on various factors, including the frequency, duration, and intensity of your workouts.

13/03/2025

🏋️Strength training is important across all age groups — from tweens and teens to adults — for several key reasons, and it plays a significant role in health and longevity.

1. Benefits for Tweens and Teens
During childhood and adolescence, strength training can help:

🦴Promote healthy growth and development: Strength training, when done properly, can help with bone density, muscle mass, and overall physical growth.
💪Enhance athletic performance: For young athletes, strength training improves muscle coordination, power, and endurance.
🧠Improve mental health: Physical activity, including strength training, has been shown to reduce stress, anxiety, and depression in adolescents.
🥙Establish healthy habits: Early exposure to exercise promotes lifelong habits that can reduce the risk of chronic diseases like obesity, diabetes, and cardiovascular issues.
😎Boost confidence and self-esteem: As teens build strength, they often feel a greater sense of accomplishment, which can improve body image and self-esteem.

2. Benefits for Adults
In adulthood, strength training provides multiple health benefits:

💪Prevent muscle loss: As we age, muscle mass naturally declines (a process called sarcopenia). Strength training helps to counteract this loss, improving strength, mobility, and functionality.
🔥Improve metabolic health: Strength training can help increase metabolism and reduce the risk of metabolic diseases like Type 2 diabetes by improving insulin sensitivity and body composition.
🦴Enhance bone health: Lifting weights stimulates bone remodeling, which increases bone density and can help prevent osteoporosis.
💪Reduce injury risk: Strengthening muscles and connective tissues helps reduce the risk of injuries, both in daily life and during other physical activities.
😀Boost mental health: Like in younger individuals, strength training can reduce symptoms of anxiety and depression and improve cognitive function.

Muscle Mass Index (MMI) and Longevity:
💪💪💪🏃🏃🏃🧓🧑‍🦳
Muscle Mass Index (MMI), which is a measure of muscle mass relative to body weight, is a strong predictor of longevity, particularly in older adults. Here’s why:

💃Indicator of overall health:
A higher MMI is often associated with better physical health, lower body fat percentage, and reduced risk of chronic conditions like heart disease, diabetes, and stroke.

🧍Preserves function and independence: Maintaining muscle mass is crucial for preventing frailty and maintaining functional independence as we age. Strong muscles are needed for mobility, balance, and the ability to perform activities of daily living.
Improves resilience: Stronger muscles help older adults recover more effectively from illness, injury, or surgery.

🦴💪Reduces risk of falls and fractures: Increased muscle strength helps maintain balance and coordination, which are vital for preventing falls in older adults, a major cause of injury and death in this age group.

In summary, strength training is essential for building and maintaining muscle mass, improving overall health, and boosting longevity. It offers lifelong benefits that start in adolescence and extend into older adulthood, making it a powerful tool for health and well-being.

06/03/2025

Around 90-95% of serotonin, the neurotransmitter often associated with mood regulation, is produced in the gut rather than the brain. The gut is home to a complex system of neurons, known as the enteric nervous system, which communicates directly with the brain through the gut-brain axis. This connection is why gut health can have such a significant impact on our mental well-being.

Certain gut bacteria also play a role in serotonin production. A balanced microbiome is thought to support optimal serotonin levels, which is why gut health is so important for overall mood and mental health.

A diverse range of fruits and vegetables is key to maintaining gut health. The variety provides different types of fiber, vitamins, minerals, and antioxidants that nourish the gut microbiome, promote digestive health, and support overall well-being. Fiber, particularly prebiotics, helps feed the good bacteria in your gut, which can aid in better serotonin production and improved mood.

Probiotic-rich foods like sauerkraut, kimchi, yogurt, kefir, and other fermented foods are also important. These foods contain live beneficial bacteria that can help balance the gut microbiome, supporting better digestion and immune function.

It could indicate that the gut isn't functioning optimally if you're struggling with gut issues, especially while exercising or competing. The stress of physical activity can sometimes exacerbate gut problems, leading to discomfort, bloating, or other symptoms. Seeking professional support could help pinpoint the root cause of these issues and develop an individualised plan to improve gut health.

Do you have any specific gut issues you're currently dealing with or ways you're trying to improve your gut health?