PMID- 10502085
OWN - NLM
STAT- MEDLINE
DCOM- 19991029
LR  - 20131121
IS  - 0301-5548 (Print)
IS  - 0301-5548 (Linking)
VI  - 80
IP  - 5
DP  - 1999 Oct
TI  - Glycerol hyperhydration improves cycle time trial performance in hot humid 
      conditions.
PG  - 494-501
AB  - Eight competitive cyclists [mean peak oxygen consumption, (VO2(peak)) = 65 ml x 
      min(-1) x kg(-1)] undertook two 60-min cycle ergometer time trials at 32 degrees 
      C and 60% relative humidity. The time trials were split into two 30-min phases: a 
      fixed-workload phase and a variable-workload phase. Each trial was preceded by 
      ingestion of either a glycerol solution [1 g x kg(-1) body mass (BM) in a diluted 
      carbohydrate (CHO)-electrolyte drink] or a placebo of equal volume (the diluted 
      CHO-electrolyte drink). The total fluid intake in each trial was 22 ml x kg(-1) 
      BM. A repeated-measures, double blind, cross over design with respect to glycerol 
      was employed. Glycerol ingestion expanded body water by approximately 600 ml over 
      the placebo treatment. Glycerol treatment significantly increased performance by 
      5% compared with the placebo group, as assessed by total work in the 
      variable-workload phase (P < 0.04). There were no significant differences in 
      rectal temperature, sweat rate or cardiac frequency between trials. Data indicate 
      that the glycerol-induced performance increase did not result from plasma volume 
      expansion and subsequently lower core temperature or lower cardiac frequencies at 
      a given power output as previously proposed. However, during the glycerol trial, 
      subjects maintained a higher power output without increased perception of effort 
      or thermal strain.
FAU - Hitchins, S
AU  - Hitchins S
AD  - Department of Physiology and Pharmacology, James Cook University, Townsville, 
      QLD, Australia. sam.hitchins@jcu.edu.au
FAU - Martin, D T
AU  - Martin DT
FAU - Burke, L
AU  - Burke L
FAU - Yates, K
AU  - Yates K
FAU - Fallon, K
AU  - Fallon K
FAU - Hahn, A
AU  - Hahn A
FAU - Dobson, G P
AU  - Dobson GP
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Germany
TA  - Eur J Appl Physiol Occup Physiol
JT  - European journal of applied physiology and occupational physiology
JID - 0410266
RN  - 0 (Solutions)
RN  - 059QF0KO0R (Water)
RN  - PDC6A3C0OX (Glycerol)
SB  - IM
MH  - Adult
MH  - *Beverages
MH  - *Bicycling
MH  - Blood
MH  - Body Water/metabolism
MH  - Glycerol/*administration & dosage
MH  - *Hot Temperature
MH  - Humans
MH  - *Humidity
MH  - Male
MH  - Osmolar Concentration
MH  - Oxygen Consumption
MH  - Plasma Volume
MH  - Solutions
MH  - Time Factors
MH  - Urine
MH  - Water/*administration & dosage
EDAT- 1999/09/29 00:00
MHDA- 1999/09/29 00:01
CRDT- 1999/09/29 00:00
PHST- 1999/09/29 00:00 [pubmed]
PHST- 1999/09/29 00:01 [medline]
PHST- 1999/09/29 00:00 [entrez]
AID - 90800494.421 [pii]
AID - 10.1007/s004210050623 [doi]
PST - ppublish
SO  - Eur J Appl Physiol Occup Physiol. 1999 Oct;80(5):494-501. doi: 
      10.1007/s004210050623.