ORIM Weekly W18 2022

EDITORIAL

As temperatures warm and outdoor activities increase, your body's energy demands shift. This week, we examine how to fuel physical activity with chronobiologically optimized nutrition, maximizing performance while supporting immune function.

Exercise and Immune Function: The J-Curve

The relationship between exercise intensity and immune function follows a J-shaped curve. Moderate exercise (150 minutes per week) reduces upper respiratory infection risk by 40-50% through enhanced immune surveillance. However, prolonged high-intensity training temporarily suppresses immunity via cortisol elevation and neutrophil redistribution. A 2021 study in Exercise Immunology Review identified the 'open window' period of immunosuppression lasting 3-72 hours post-exhaustive exercise.

Carbohydrate Periodization for Athletes

The concept of 'fueling for the work required' has replaced static macronutrient ratios. Research in the British Journal of Sports Medicine (2021) demonstrated that training with varied carbohydrate availability on different days enhanced metabolic flexibility and fat oxidation capacity. High-carb days before intense sessions and low-carb days during recovery optimized both performance and body composition simultaneously.

Post-Exercise Nutrition Timing Windows

The anabolic window after exercise is wider than previously believed. A 2021 meta-analysis in the Journal of the International Society of Sports Nutrition found that consuming 20-40g protein within 4 hours post-exercise maximized muscle protein synthesis, rather than the previously claimed 30-minute window. However, carbohydrate replenishment within 2 hours remains important for glycogen resynthesis.

Beetroot (Beta vulgaris) for Performance

Beetroot juice has become the evidence-backed ergogenic aid of choice for endurance athletes. Its dietary nitrates convert to nitric oxide, improving oxygen efficiency by 3-5% and time-trial performance by 1-3%. The effect is most pronounced in recreational athletes and at altitude. A 2021 study showed benefits appear after just 6 days of supplementation with 500ml daily beetroot juice.

Drink 500ml beetroot juice 2-3 hours before exercise for peak nitric oxide conversion. Avoid mouthwash before consuming, as oral bacteria are essential for the nitrate-to-nitrite conversion step.

THIS WEEK IN BRIEF

► SPORT: Tokyo 2020 Olympic nutrition data reveals that 60% of medal-winning endurance athletes used beetroot juice supplementation as part of their competition preparation protocol.

► INNOVATION: Swiss sports nutrition company Sponser launches a whole-food energy gel made from dates, rice, and salt, replacing synthetic alternatives with bioavailable ingredients.

► RESEARCH: University of Lausanne study demonstrates that exercising in nature (green exercise) produces 25% greater cortisol reduction than equivalent indoor gym workouts.

ORIM Tip: Never try a new food on race day or before an important training session. Your gut needs familiarity under stress. Practice your pre-event nutrition during training to identify what works for your individual digestive system.