Effect of glucose polymer diet supplement on responses to prolonged successive swimming, cycling and running.
Fifteen male endurance athletes were studied to determine the effect of a glucose polymer (GP) diet supplement on physiological and perceptual responses to successive swimming, cycling and running exercise. Thirty min of swimming, cycling and running at 70% VO2max, followed by a run to exhaustion at 90% VO2max was performed after one week of training under two dietary conditions: 1) GP (230 g of GP consumed daily) and 2) placebo (P, saccharin-sweetened supplement consumed daily). During GP, daily carbohydrate (CHO) intake was higher (p less than 0.05) by 173 g or 14% of energy intake than during P, but total energy intake was not significantly different. During 90 min of exercise, CHO utilization and blood glucose were significantly higher under GP than P by an average of 20.2% and 14.5%, respectively, but heart rate, ventilation, oxygen uptake, ratings of perceived exertion, and plasma lactate were not different. Run time to exhaustion at 90% VO2max was significantly longer by 1.2 min (23%) under GP. The results suggest that a GP diet supplement may be of value during endurance exercise by increasing the availability of CHO.
Millard-Stafford
M L
ML
Department of Physical Education, University of Georgia, Athens 30602.
Cureton
K J
KJ
Ray
C A
CA
D001642:Bicycling; D001786:Blood Glucose / Q000032:analysis; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage* / Q000378:metabolism; D005936:Glucans / Q000008:administration & dosage* / Q000378:metabolism; D006801:Humans; D008297:Male; D005082:Physical Exertion; D012420:Running; D013550:Swimming
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D005936:Glucans