The Importance of Hydration in the Human Spring Mechanism

In the last post I discussed how my list of injuries has weakened the spring capabilities of my body and the impact of poor self-treatment. The strain to my left calf happened because I was not properly hydrated. This segment will cover much of the impact hydration plays on human spring performance. Much of this information will come from the Position Statement on Fluid Replacement of the National Athletic Trainers Association, one study from the Journal of Athletic Training, and two other articles.

The Position Statement of the National Athletic Trainers Association says that both a lack of adequate fluid replacement, or “hypohydration”, and excessive intake, or “hyperhydration”, can compromise athletic performance and increase health risks. Hypohydration, even at a modest level of 2%, can compromise athletic performance, maximization of the transfer of metabolic heat, mood, and recovery from exercise. Extreme deviations on either end of the physiological range can compromise health and organ function, which is why it is important to quantify sweat rates during physical activity in different environments and practice necessary fluid-replacement before, during, and after physical activity.

Figure 15: Signs of Dehydration

The Position Statement also notes that more than 50% of athletes at all levels (youth through professional) arrive to workouts hypohydrated. When access to fluids based on thirst and voluntary fluid intake is adequate during activity, humans replace roughly 2/3 of sweat losses. Maintaining hydration status with minimal variation (+/- 1%) allows the body to optimally thermoregulate and maintain cardiovascular function. On the other hand, excessive fluid consumption can lead to life-threatening exercise-associated hyponatremia (EAH), in which extracellular body water enters the cells and causes organ and tissue swelling. Although uncommon in team-sport athletes, this has been found in 10% - 20% of distance athletes after events. This condition is fatal when the brain cells swell and brain tissue herniates, or when the swelling triggers noncardiogenic pulmonary edema that leads to respiratory failure. Therefore, it is imperative that hydration remain at a safe level. For more information from the Position Statement, visit their link here.

According to the article “Dehydration and What It Does to Your Muscles and Body”, water makes up 73% of the brain and heart, 64% of skin, 79% of muscles and kidneys, and 31% of bones. Because water makes up a large portion of muscles, dehydration lowers their performance and elasticity, decreasing the efficiency of the overall human spring. This is why my calf strain happened! Dehydration can also make pain levels worse, usually taking the form of headaches, muscle aches, arthritic pains, back pains, and more. On another note, a in certain study to determine the effects of dehydration on drivers, it was found that the dehydrated drivers showed similar patterns to those driving under the influence of alcohol (unnecessary lane shifting, delayed reaction time in braking). This is because of the large makeup of water of the brain. So, if the brain is responsible for tuning the muscles for impact to the human spring, dehydration would therefore cause a slight delayed reaction time in tuning, making the spring even less effective than the loss of muscle elasticity. You can read more of this article here.

Another article, “Here’s What Happens to Your Body When You’re Dehydrated”, mentions that a human’s thirst mechanism falls behind the actual level of hydration. Ensuring necessary fluid replacement practices is necessary to staying hydrated for game day (and practice time). It is common that athletes aren’t trained to drink water when they aren’t thirsty. If our brains aren’t telling us to drink more water, then they will be focused on something else, most likely on school, work, or other things we stress about. The link for this article is found here.

In the study “Rehydration Capacities and Rates for Various Porcine Tissues after Dehydration”, the researchers’ results suggested that the initial level of dehydration plays a role in the ability of tissues to rehydrate. The results additionally found that significant decreases in the liquid mass fraction after complete rehydration were found in lung, tendon, fat, and muscle tissue when previously experiencing a 30% - 40% loss in mass from dehydration; basically, if a tissue becomes too hydrated, it may permanently lose its capacity to rehydrate to the initial liquid volume, and thus having a lasting impact on the human spring. Lastly, hydration behaviors varied between tissue types, meaning different tissues will rehydrate faster than others. This further necessitates the need for proper fluid replacement practices.

What I’ve found is that the lack of water causes tissues to become less elastic and spring-like. Spring properties are entirely dependent on the elasticity of a material, hence their spring constants in Hooke’s Law (force = spring constant * displacement), or Young’s Modulus in deformation equations. This can lead to the human spring’s inability to absorb impact from running, take the impact from a tackle, and prevent against injury.

A lot of stress on the body can wear it out, but the nice thing is our bodies are naturally made to recover. The next segment is about how rest and sleep play an important role in the development of an athlete and the health of the human spring.

The link for the study “Rehydration Capacities and Rates for Various Porcine Tissues” is found here.