The Effect of Acute Hyperglycemia on Muscular Strength, Power and Endurance

The purpose of this study was to elucidate the impact of acute hyperglycemia on skeletal muscle strength, power, and endurance. Ten male collegiate athletes (age 21.5 ± 1.5 years, height 186 ± 2.03 cm, body mass 108.8 ± 7.6 kg) participated in 2 testing sessions, separated by 7 days and randomized for either high glucose (HG) or control (C) treatment conditions. HG consumed a high glucose drink (2 g glucose/kg body weight) while controls consumed an isocaloric nutrition bar (40% protein, 30% fat, and 30% carbohydrate). Blood glucose (BC) levels for HG and C were tested at 0 (basal) and 30, 60, 90, and 120 minutes (mins) post consumption. At 30 mins post consumption, HG and C muscular strength was assessed by a 1RM bench press (BP) test followed by lower body power at 60 mins via vertical jump test. Muscular endurance was examined with a 3-set-to-failure BP test at 90 mins. HG exhibited significantly greater BC values (p<0.05) at the 30, 60, 90, and 120 minute time points. HG glucose area under the curve was significantly greater (p<0.05) than C and was positively correlated with %body fat, a finding that trended towards significance, r = 0.587, n= 10, p = 0.074. There were no between group differences in maximal strength, power or muscular endurance. Although performance measures were unaffected by acute hyperglycemia, acute hyperglycemia can be induced and maintained in healthy, active and young subjects. Despite regular physical activity, excess body fat negatively impacts glucose metabolism.