As long as we are on the topic of toenails, we need to review the effects of dehydration on our skin, which includes toenails. This subject is often overlooked by athletes.
Dehydration and the loss of important electrolytes can have a negative effect when hours of physical exercise cause stress to the extremities as fluid accumulates in the hands and feet. Fingers and toes often swell as they retain fluid because of low blood sodium (hyponatremia). This causes foot problems as the soft, waterlogged tissues become vulnerable to the rubbing and pounding as we continue to run and hike.
Make sure that you replace electrolytes, especially on long events. Drinking water or even sports drinks may not provide the proper replacement of sodium and other important electrolytes. The popular energy bars and gels may also be low in the electrolytes needed by the body.
Karl King, developer of the SUCCEED! Buffer/Electrolyte Caps, points out that the maintenance of proper electrolyte levels will reduce swelling of hands and feet even after many hours of exercise, and reduce “hot spots” and blisters on the feet. “When there is heat and humidity, the sweat rate is high and sodium is usually lost in significant amounts,” he says. “The sodium comes from the blood stream, and when the plasma gets too low, the body reacts to maintain the minimal tolerable level by pushing water from the blood into extracellular spaces. Thus, hands and feet swell. When the tissue on the feet swells, the feet become soft and more susceptible to blisters and damaged toenails. The feet swell inside the running shoes, putting extra pressure on the tissues, and those tissues can be rubbed to the point of physical damage. We see blisters form as layers of skin separate, and we see toenails move more, damaging the weakened tissues that normally anchor them.”
Ultrarunner Jay Hodde, a Badwater veteran, notes, “Proper hydration and well hydrated should not be used interchangeably. Being well hydrated with fluids says nothing about the sodium content of the fluid; both are important.” When you are well hydrated yet have low sodium, extra fluid accumulates in the tissues of the feet and the likelihood of blister formation increases. When you become fluid-deficient, the skin loses its normal levels of water and in turn loses its turgor. Then it easily rubs or folds over on itself, which leads to blisters.
Ultrarunner Rod Dalitz says, “I am convinced that electrolyte balance may be a big factor in blisters. With too much or too little salt, the layer just under the skin swells, and your skin is easier to disconnect from underlying tissue – which makes a blister.” Many athletes have found out the hard way that simply drinking a fluid replacement drink often will not provide the necessary electrolytes in the proper concentrations that the body needs. The use of a sodium replacement product in prolonged physical activity can help in the prevention of blisters.
Electrolytes and Black Toenails
Karl King emphasizes, “Black toenails are often a result of insufficient electrolyte management. Too little sodium makes hands AND feet swell. You can see your hands, but you can’t see it happening with your feet because they are in your shoes. When the tissues swell because they have excess water, the mechanical strength of the nail footing goes down. Then any movement will do tissue damage. Most of the damage is done in the second half of an ultra when electrolyte status is often thrown off if you don’t take care of it. Not many people get black toenails from a 15-mile run. Before I figured out electrolytes, I had black toenails like all of my ultra friends. After improving the way I handled electrolytes, my toenails gradually healed and black toenails were a thing of the past.”
Whether you have a 100 mile race on your calendar, or a 50 miler, or a marathon, make sure you manage your electrolytes and hydration level.
