What a research paper says about rehydration after training
Welcome to Grappling Lane #8! This week’s issue is all about rehydrating yourself after training.
Let’s go 👊
As I was wondering what the best strategy is to rehydrate in order to maximise recovery after a hard evening session, I stumbled upon this paper: National Athletic Trainers’ Association Position Statement: Fluid Replacement for the Physically Active
A little bit overkill? For sure. Did I finish it? For sure. Do I need to go out more? For sure.
On rehydrating, notes from smart people
Individuals should not gain body mass during exercise (from pre-exercise to post exercise) unless they begin activity with an unavoidable fluid deficiency. Hyper hydration confers no physiological or performance advantages and is not recommended. TLDR: Bulking up on water during training doesn’t help.
It’s really hard to give universal recommendations about how much should be consumed. There are multiple factors involved in fluid balance: age, altitude, temperature, body size, exercise intensity, acclimatisation status, environmental stress.
Calculating your body mass change is a quick and effective way to track hydration status. You should compare is with at least 3 consecutive days where your body was hydrated. Body mass should be used as an objective hydration measure by physically active individuals and clinicians to ensure maintenance of hydration status.
Free-living individuals habitually consume on average over 2L/day (ranges are between 0.5L and 4.0L!). Despite large variations in fluid intake, body water volume and hydration status, biomarkers in the blood remain in a tight range due to the wide normal range of the body’ capacity to concentrate the urine.
An athlete should consume enough fluid to approximate personal sweat volume losses and avoid both excessive body fluid losses and overconsumption of fluids.
After 50, your thrist sensitivity might decrease when the loss of body water is uncompensated.
Beverage additives
Under normal circumstances, physically active people consuming a well-balanced diet should not need to add specific ingredients to their fluids before, during, or after activity.
As a general rule, physical activities lasting less than 1 hour should require no substances other than water. For over 1h, there might be a benefit from adding carbohydrates or electrolytes to rehydration fluids, especially in extreme environments.
Creatine has been studied extensively due to stated cramps and dehydration episodes, but at recommended doses, creatine does not compromise hydration status.
Caffeine may increase short-term urine production at rest but does not induce diuresis during exercise. Athletic trainers should not discourage mild or moderate (approx 3mg/kg) caffeine consumption before and every 30 minutes during exercise on the basis of diuretic effects.
Using sodium tablets before or during activity to prevent dehydration presents little evidence to support it.
TLDR
If you do 1 hour sessions, you should not need electrolytes. If you train multiple times a day or join open mats for 1h+, electrolytes and carbohydrates might be a good solution.
If you want to know how much you should drink, measure yourself before and after training and monitor your total volume of water consumed during training (and if possible, don’t pee to make it more accurate)
I had over 2L of water loss after a 90 minute session that was mostly rolling.Bulking up on water before or during training does not bring any physical advantages.
In addition to water, ingesting carbs and protein after exercise provides substantial benefits by restoring the muscle glycogen and facilitating muscle recovery.
That’s it for this week! If you found this useful (or not) let me know, as well as anything else you want me to research.
Elsewhere on the web
Really awesome documentary on the guy that can both stream games and arm bar a guy while suplexing him.