Orienteering performance andingestion of glucoseand glucosepolymers

Summary Thebenefit ofglucose polymer ingestion inaddition to2.5 percentglucose before andduring aprolonged orienteeringcompetition wasstudied. Thefinal timeinthecompetitioninthegroupingesting 2.5percentglucose (group G, n=10)was113min37s±8min11s,andinthegroupwhich hadadditionally ingested glucose polymer (group G+GP, n=8)107min18s±4min41s(NS). Onefifth (21percent) of thetimedifference between thetwogroups wasduetodifference inorienteering errors. GroupG+GP orienteered thelastthirdofthecompetition faster thangroupG (p<0.05). Thetimeratio betweenthelastthirdofthe competition andthefirst third ofthecompetition waslower ingroupG+GP thaningroupG (p<0.05). After thecompetition, there wasstatistially insignificant tendency to higherserumglucose andlowerserumfreefatty acid concentrations ingroupG+GP,andseruminsulin concentration washigheringroupG+GP thaningroupG (p<0.05). Threesubjects reported that theyexhausted duringthecompetition. Thesesamethree subjects hadthelowestserumglucose concentrations after thecompetition (2.9 mmol.1-', 2.9mmol.1-', 3.5mmol.l-') andallofthemwere fromgroupG.Itisconcluded thatglucose polymer syrup ingestion isbeneficial forprolonged psychophysical performance.