Summary and Key Practical Recommendations 

From the areas outlined in this article, it is clear that with hydration levels and fluid losses during exercise come high levels of variability between athletes. There is no ‘one size fits all’ advice that can be given. Many environmental and physiological variables need to be considered on a daily basis in order to develop a comprehensive strategy to facilitate performance. Here is a summary for athletes and sports nutrition practitioners to assist in hydration preparations:


  • Hydration status can be assessed daily and even hourly by using pee chart comparisons. When a greater degree of accuracy is required, urine osmolality measures are recommended.


  • To estimate fluid losses during training, begin the session in a hydrated state, and assess the total loss in body mass at the end of the session. Use this method in varying environments to create a more comprehensive strategy to fit any environmental differences that could arise.


  • Use the formation of salt crystals on black clothing as a guide to assessing the degree of salt replacement necessary for the athlete.


  • Design the strategy well before competition day. Allow plenty of time to experiment with changes to the approach to hydration.


  • Avoid big changes on competition day. Even the smallest difference to your personal strategy could disrupt your plans. Are you consuming the same flavor of sports during on race day as you have been during training? Is the concentration of carbohydrates similar to what you have been previously accustomed to?


  • Finally relax, and enjoy your competition! After all the preparations you have put in, you should allow yourself to focus on your performance! Good luck!


Hope you enjoyed this in depth Science Corner Series about hydration and physical performance!

If you wish to take a look at any of the original scientific studies I’ve also attached the list (References) below too!



Reference/ Scientific Study List

1. Morton J P et al. (2010). Making the weight: a case study from professional boxing. International Journal of Sports Nutrition and Exercise Metabolism, 20 (1), 85-85.
2. Galloway SD & Maughan RJ. Effects of ambient temperature on the capacity to perform cycling exercise in man. Med Sci Sport Exerc 1997: 27 : 1240-9.
3. Maughan RJ, Leiper JB. Fluid replacement requirements in soccer. J Sports Sci 1994: 12: S29-S34
4. Noakes 2007. Hydration in the marathon. Using thirst to gauge safe fluid replacement. Sports Med. 37. 463-66.
5. Dawson et al. (1985). Physiological and performance responses to playing tennis in a cool environment and similar intervalized treadmill running in a climate. Journal Human Move Studies. 11 (21-34)
6. Pfeiffer et al. (2012). Nutritional intake and gastrointestinal problems during competitive endurance events. Medicine and Science in Sport and Exercise, 44 (2), 344-351.
7. Maughan et al. (2004). Fluid and Electrolyte intake and loss in elite soccer players during training. International journal of sports nutrition and exercise metabolism. 14. (327-340).
8. Kavouras et al. (2011). Educational invervention on water intake improveshydration status and enhances exercise performance in athletic youth. Scandinavian Journal od Medicine and Science in Sports. 22 684-689.
9. Sharma et al. 1986. Influence of heat-stress induces dehydration on mental functions. Ergonomics 29 791-799.
10. Wilson et al. An Alternative dietary strategy to make weight while improving mood, decreasing body fat, and not dehydrating: A case study of a professional jockey. Int Jnl Spo Nut and Ex Met. 22, 225-231.