Dehydration: It's Not Just About Quantity, But Quality Too
Staying hydrated through drinking plenty of liquid is important for everyone, but it’s vital for those who regularly take part in sporting activities.
Common sense advice from coaches and trainers is to drink plenty of fluid while exercising, because the negative effects of dehydration on athletic performance are well-known. We’re all accustomed to seeing leading athletes topping-up their fluid at half time or during breaks in the game. It’s even become an established ritual in some sports. Think of Wimbledon, and the classic barley water that’s long been associated with tennis comes immediately to mind.
New studies reveal the impact of dehydration
Interestingly, though, until recently far less was known in-depth about the physiological effects of dehydration on the body. New studies show how much it impacts on athletic performance, by affecting not only physical but also cognitive functions. What’s more, those studies are revealing that it’s not just how much you drink, but what you drink and even when you drink it that makes a difference to performance and recovery. That applies to water as well as the various types of specialist sports drinks that are now so widely available.
Human beings consist of 55%–65% water, while infants are truly water babies – they are composed of 75% water! It’s no wonder, then, that even brief spells of dehydration can produce such negative effects. This precious liquid is necessary for all our intra- and extracellular health. It dilutes where needed, carries vital nutrients, keeps our organs functioning and is a critical part of the body’s cooling system.
Thermoregulation, or the way in which we keep our bodies at the right temperature, is controlled by water loss. During intensive exercise, the muscles and other organs produce heat that has to be removed, which is done through perspiring and exhaling. If we don’t constantly replace those losses, we suffer from dehydration, also known as hypohydration.
Low level hypohydration can cause cognitive issues
One study in a leading journal devoted to nutrition and food science examined just how effective alkaline water was in hydrating athletes. The researchers concluded that even very low levels of hypohydration, 2% for example, could cause issues with cognition. Athletes suffering from hypohydration were less aware and alert. Even their arithmetic skills and psychomotor skills were affected at that level of dehydration.
Some athletes, such as cyclists, marathon runners and soccer players, have been considered to be particularly at risk, because of the aerobic intensity of their sports. Such sports now have a global following and may be played or carried out in widely varying ranges of temperature and humidity, over extended periods of time. Athletes need to be constantly aware of the need for correct re-hydration related to the particular circumstances of the game or match – something that it’s easy to lose sight of in the excitement and achievement of the moment.
Track and field events, from short sprints to shot put, have been considered to be less influenced by the hydration levels of the athlete, since they are designated “explosive” sports which do not involve the same degree of intensive and lengthy exercise. However, research indicates that certain types of water can have a beneficial effect on participants in anaerobic sports as well as aerobic ones. The right hydration matters for all athletes – so which is the best drink?
Water: still the drink of choice, but what type?
In fact, good old water is still the first choice for many athletes. Even here, though, choice can make significant difference to performance. One study, published in a leading journal devoted to the biology of sport, looked at the effects on young footballers of drinking mineral-based alkaline water after exercise. One of their conclusions was that alkaline mineral water of high pH value had a beneficial effect on the acid-base balance of the body, assisting in increasing the lactate utilization rate after anaerobic exercise, which is important for athletic recovery.
Other research had noted that water retention at the end of recovery was higher when subjects drank alkaline water. This was tested against a control group taking a placebo. The evidence is gathering to support the idea that alkaline water really does offer better hydration.
Can alkaline water really make such a difference?
Small differences in alkalinity and mineral content can and do make a significant difference. One of the research conclusions was that even low-level changes within the body's tissues and blood circulation could have significant effects on the metabolism, including reactions to the stress caused by oxidation.
Why should this be?
One of the effects of intense exercise that pushes the athlete beyond the optimal maximum is an increase in what are known as reactive oxygen species (ROS), as well as reactive nitrogen species (RNS). Alkaline water appears to assist in neutralizing ROS through inhibiting production and repairing damage. It may even have a positive effect in preventing metabolic diseases. Ultimately, for both athletes and non-athletes, whether involved in advanced aerobic or anaerobic exercise or not, alkaline water is about correcting the acid-base of the body.
How much liquid intake do athletes need?
One of the key points emerging from all the studies into alkaline water is that intake should meet the needs of each individual. Multiple factors come into play, such as weather conditions, including humidity, at the time of exercise, as well as age, experience and body mass of participants. One thing is clear: staying hydrated and recovering well after active sport is not just about the quantity of liquid intake but also its quality. Drinking alkaline water, whether mineral or ionized, really does make a difference, the studies suggest.