Tags

Type your tag names separated by a space and hit enter

Comparison of short-term aerobic training and high aerobic power on tolerance to uncompensable heat stress.
Aviat Space Environ Med. 1999 Jul; 70(7):637-43.AS

Abstract

This study investigated whether, in subjects of moderate aerobic fitness, short-term aerobic training could replicate the improved physiological responses to exercise-heat stress observed in individuals with a high level of aerobic fitness. Males of moderate (MF; <50 ml x kg(-1) min(-1) VO2peak, n = 8) and high (HF; >55 ml x kg(-1) x min(-1) VO2peak, n = 8) aerobic fitness walked at 3.5 km x h(-1) in the heat (40 degrees C, 30% relative humidity) wearing nuclear, biological, and chemical protective clothing. Tests were conducted once on HF subjects and on MF subjects before (MF-Pre) and after (MF-Post) a 2-week program 6 d x week(-1) of daily aerobic training (1 h treadmill exercise at 65% VO2peak for 12 d, 22 degrees C, 40% relative humidity). The training significantly increased VO2peak by 6.5%, while heart rate (fc) and rectal temperature (Tre) rise decreased during exercise in a thermoneutral environment. HF had lower body mass and body fat content than MF, and VO2peak remained lower in MF pre-or post-training. In the heat, MF-Post had a decreased skin temperature (Tsk) and an increased sweat rate compared with MF-Pre, but no changes were observed in fc, Tre, or tolerance time (TT). No significant differences during the first 60 min in Tre and fc were observed between the MF-Post and the HF subjects, though the HF subjects exhibited a lower Tsk. The endpoint Tre, deltaTre, and TT remained significantly higher in HF than in either the MF-Pre or MF-Post subjects. It was concluded that, in preparation for exercise in an uncompensable heat stress environment, short-term aerobic training offers little, if any, benefit and is not an adequate substitute for a high level of aerobic fitness resulting from habitual exercise and training.

Authors+Show Affiliations

Defence and Civil Institute of Environmental Medicine, Human Protection and Performance Section, Toronto, Ont., Canada.No affiliation info available

Pub Type(s)

Comparative Study
Journal Article

Language

eng

PubMed ID

10416998

Citation

Cheung, S S., and T M. McLellan. "Comparison of Short-term Aerobic Training and High Aerobic Power On Tolerance to Uncompensable Heat Stress." Aviation, Space, and Environmental Medicine, vol. 70, no. 7, 1999, pp. 637-43.
Cheung SS, McLellan TM. Comparison of short-term aerobic training and high aerobic power on tolerance to uncompensable heat stress. Aviat Space Environ Med. 1999;70(7):637-43.
Cheung, S. S., & McLellan, T. M. (1999). Comparison of short-term aerobic training and high aerobic power on tolerance to uncompensable heat stress. Aviation, Space, and Environmental Medicine, 70(7), 637-43.
Cheung SS, McLellan TM. Comparison of Short-term Aerobic Training and High Aerobic Power On Tolerance to Uncompensable Heat Stress. Aviat Space Environ Med. 1999;70(7):637-43. PubMed PMID: 10416998.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Comparison of short-term aerobic training and high aerobic power on tolerance to uncompensable heat stress. AU - Cheung,S S, AU - McLellan,T M, PY - 1999/7/23/pubmed PY - 1999/7/23/medline PY - 1999/7/23/entrez SP - 637 EP - 43 JF - Aviation, space, and environmental medicine JO - Aviat Space Environ Med VL - 70 IS - 7 N2 - This study investigated whether, in subjects of moderate aerobic fitness, short-term aerobic training could replicate the improved physiological responses to exercise-heat stress observed in individuals with a high level of aerobic fitness. Males of moderate (MF; <50 ml x kg(-1) min(-1) VO2peak, n = 8) and high (HF; >55 ml x kg(-1) x min(-1) VO2peak, n = 8) aerobic fitness walked at 3.5 km x h(-1) in the heat (40 degrees C, 30% relative humidity) wearing nuclear, biological, and chemical protective clothing. Tests were conducted once on HF subjects and on MF subjects before (MF-Pre) and after (MF-Post) a 2-week program 6 d x week(-1) of daily aerobic training (1 h treadmill exercise at 65% VO2peak for 12 d, 22 degrees C, 40% relative humidity). The training significantly increased VO2peak by 6.5%, while heart rate (fc) and rectal temperature (Tre) rise decreased during exercise in a thermoneutral environment. HF had lower body mass and body fat content than MF, and VO2peak remained lower in MF pre-or post-training. In the heat, MF-Post had a decreased skin temperature (Tsk) and an increased sweat rate compared with MF-Pre, but no changes were observed in fc, Tre, or tolerance time (TT). No significant differences during the first 60 min in Tre and fc were observed between the MF-Post and the HF subjects, though the HF subjects exhibited a lower Tsk. The endpoint Tre, deltaTre, and TT remained significantly higher in HF than in either the MF-Pre or MF-Post subjects. It was concluded that, in preparation for exercise in an uncompensable heat stress environment, short-term aerobic training offers little, if any, benefit and is not an adequate substitute for a high level of aerobic fitness resulting from habitual exercise and training. SN - 0095-6562 UR - https://www.unboundmedicine.com/medline/citation/10416998/Comparison_of_short_term_aerobic_training_and_high_aerobic_power_on_tolerance_to_uncompensable_heat_stress_ L2 - https://medlineplus.gov/exerciseandphysicalfitness.html DB - PRIME DP - Unbound Medicine ER -