CONSEQUENCES OF DEHYDRATION
CONSEQUENCES OF DEHYDRATION
ARE YOU AT YOUR BEST?
Studies show that up to 87% of endurance athletes are physically impaired during their workouts and competitions due to dehydration, despite ample access to fluids. Dehydration causes the following physiological phenomena:
- DECREASED BLOOD PRESSURE
- INCREASED HEART RATE
- INCREASED RESPIRATORY RATE
- DECREASED BLOOD FLOW TO EXTREMITIES
These physiological changes can lead to cardio-respiratory stress, impaired thermoregulation, and fatigue – all of which have a significant impact on athletic performance.
Because the symptoms of mild dehydration are subtle – often imperceptible – athletes suffer the consequences without always knowing it.
"For lack of a better method, athletes are forced to drink to thirst – a notoriously poor marker of hydration status."
"For lack of a better method, athletes are forced to drink to thirst – a notoriously poor marker of hydration status."
FINISH STRONG OR STRUGGLE?
Proper hydration is central to feeling energized and motivated. Fatigue and physiological strain manifest at dehydration levels as low as 2%, making a workout feel sluggish and heavy-legged. This not only leads to an athlete feeling flat and listless, but also compromises the quality of the workout and training potential.
Studies show a significant drop in performance at mild dehydration levels as low as 2-3%. This impairment manifests itself in multiple ways.
ENDURANCE
For endurance athletes, dehydration causes the heart to work harder and decreases an athletes VO2max —the maximum oxygen uptake. This causes oxygen depletion in the muscles and, therefore, suboptimal endurance.
STRENGTH
Electrolyte depletion often occurs with dehydration. Electrolytes such as calcium, chloride, magnesium, phosphorous, potassium and sodium carry an ionic charge and support muscle function. When electrolytes are depleted, it results in muscle weakness and potentially contributes to cramping.
COGNITIVE
Low body water and electrolyte levels compromise the transmission of nerve impulses in the brain, and between the brain and the muscles. Impaired neuromuscular signaling leads to delayed response times, poor judgment, mental confusion, and fatigue.
*Sources: Armstrong 1985; Pinchan 1988; Maughn 1991; Sawka 1990; Sawka 1985; Sawka 1992; Del Coso et al, 2013