Water is arguably THE most critical nutrient in our bodies. Don’t drink it for long enough and you die. We’re made up of roughly 60-70% water (depending on which research you go by), with muscle tissue composed of between 75-85% water (again, depending on sources). As part of the blood stream water helps carry nutrients toward cells and away as waste products. Unlike a lot of nutrients in the body, water can’t be created or stored. It has to be replenished once it is lost through urine, sweat, and respiration. Functions of water go further than transportation of nutrients; water also regulates normal body temperature and blood volume amongst other things.
WHY DO WE CARE?
As powerlifters or strength athletes, hydration plays a large role in performance, functions of water go further than transportation of nutrients; water also regulates normal body temperature and blood volume amongst other things. A study published in the Journal of Strength and Conditioning Research (Schoffstall et al., 2001) reported that ‘dehydration resulting in approximately 1.5% loss of body mass adversely affects bench press 1RM performance’. They also noted that the negative effects of dehydration on strength were overcome by a 2 hour rest period and water consumption - valuable information for those who do harsh water cuts to make weight.
A review of literature conducted by Judelson et al., (2007) found that dehydration limits strength, power, and high-intensity endurance and so is an important factor to consider when attempting to maximise muscular performance in athletic settings. Other studies have shown that fluid loss as low as 2% of total body weight reduces endurance capacity and aerobic performance. Increased levels of dehydration cause impaired mental concentration, alertness, muscular strength and endurance. All of which will alter an athletes athletic performance. In summary, it pays to be well hydrated in a sport where a fractional decrease in performance can cost you a placing in competition or progress in training.
HYDRATION DURING TRAINING
For training sessions of moderate intensity that last less than an hour, water is the most appropriate fluid to hydrate. You’re not likely to need added carbohydrates during these training sessions. Events or training sessions that are moderate to high in intensity and/or load, we’d recommend hydrating with a sports drink (or added carbohydrates to your water i.e. dextrose) containing 4-8% carbohydrates (i.e. 40-80g dextrose in 1L water) or 30-60g per hour to delay fatigue. Thirst isn’t a good guide for dehydration; most athletes won’t begin to feel thirsty until they’ve lost about 1-2% of their body weight in water – by this point they’ll be experiencing negative impacts on performance.
Fluids before training shouldn’t be a high concentration of sugar. The more concentrated the fluid the longer gastric emptying. Resulting in a delay of fluid absorption and utilization. Sports drinks or sugary drinks used pre/during training or competition should ideally be diluted 50% to prevent this. Studies show that fluid absorption rates range from 0.8–1.2 litres per hour, meaning that pre-workout hydration is crucial. Concentrated sports drinks can be used after training to replace glycogen stores in muscle and liver, as well as fluid and electrolyte levels.
For those of you in the UK lockdown wanting to be extra accurate and have something to do, you can weigh yourself before and after each training session so you know exactly how much to drink afterward to recover the fluids lost during training. Weight loss will be fluid loss (provided you take into account any powders i.e. creatine, dextrose etc. in your intra workout drink as well as the weight of the liquid you drink). Sweat loss during training can vary anywhere from 1.0-1.5 litres per hour. Fluids lost during training or competition should be replaced completely within a 6 hour span from the completion time of training. Another take on this looks at studies that have suggested consuming 1.0 to 1.5 ml of fluid per calorie expended during training as this is optimal to regain hydration lost from training. Therefore an athlete who burns 1000 calories during a training session should consume at a minimum 1.0- 1.5L to return to pre-training fluid balance.
Every athlete’s body has different requirements; there isn’t one set of guidelines which is perfect for every individual. Amounts will vary depending on training load, how the body responds to hydration levels, athlete bodyweight, etc. Either way, there isn’t any excuse for poor hydration!
References
Judelson, D.A., Maresh, C.M., Anderson, J.M., Armstrong, L.E., Casa, D.J., Kraemer, W.J. and Volek, J.S., 2007. Hydration and muscular performance. Sports medicine, 37(10), pp.907-921.
Schoffstall, J.E., Branch, J.D., Leutholtz, B.C. and Swain, D.E., 2001. Effects of dehydration and rehydration on the one-repetition maximum bench press of weight-trained males. Journal of strength and conditioning research, 15(1), pp.102-108.