LAUSR

Szymanski, M, Miller, KC, O’Connor, P, Hildebrandt, L, and Umberger, L. Sweat characteristics in individuals with varying susceptibilities of exercise-associated muscle cramps. J Strength Cond Res XX(X): 000–000, 2020—Many medical professionals believe dehydration and electrolyte losses cause exercise-associatedmuscle cramping (EAMC). Unlike prior field studies,we compared sweat characteristics in crampers and noncrampers but accounted for numerous factors that affect sweat characteristics including initial hydration status, diet and fluid intake, exercise conditions, and environmental conditions. Sixteen women and 14men (mean6SD; age5 216 2 year, body mass569.1611.6 kg, height5 171.469.9 cm) self-reported either noEAMChistory (n58), lowEAMChistory (n5 10), or highEAMC history (n5 12). Wemeasured V̇O2max, and subjects recorded their diet. At least 3 days later, subjects ran at 70% of their V̇O2max for 30 minutes in the heat (39.9 6 0.6 ̊ C, 36 6 2% relative humidity). Dorsal forearm sweat was collected and analyzed for sweat sodium concentration ([Na]sw), sweat potassium concentration ([K ]sw), and sweat chloride concentration ([Cl ]sw). Sweat rate (SWR) was estimated frombodymassandnormalizedusingbody surfacearea (BSA).Dietary fluid,Na, andK ingestionwasestimated froma3-day diet log.We observed no differences for any variable among the original 3 groups (p5 0.05–p5 0.73). Thus, we combined the high and lowcrampgroups and reanalyzed the data against the noncramping group. Again, therewere no differences for [Na]sw (p5 0.68), [K ]sw (p5 0.86), [Cl]sw, (p5 0.69), SWR/BSA (p5 0.11), dietary Na + (p5 0.14), dietary K (p5 0.66), and fluid intake (p5 0.28). Fluid and electrolyte losses may play a more minor role in EAMC genesis than previously thought.