Effect of short-term heat acclimation training on kinetics of lactate removal following maximal exercise

Details

• Personal Author:
  Coca, Aitor ; DiLeo TD ; Kang HK ; Kim J-H ; Powell JB ; Roberge RJ
• Description:
  BACKGROUND: Heat acclimation (HA) evokes numerous physiological adaptations, improves heat tolerance and has also been shown to enhance lactate (LA) responses during exercise, similar to that seen with endurance training. The purpose of this study was to examine whether HA improves the body's ability to remove LA during recovery following maximal exercise. METHODS: Ten healthy men completed two trials of maximal treadmill exercise (pre- and post-HA) separated by 5 days of HA. Each day of HA consisted of two 45 minute periods of cycling at approximately 50% VO2max separated by a 15min rest period in an environmental chamber (Tdb 45 degrees C, RH 20%). In pre-/post-HA trials, venous blood was collected during 60 minutes of recovery to determine LA concentrations and removal kinetics (A2: amplitude and y2: velocity constant) using bi-exponential curve fitting. RESULTS: Physiological adaptation to heat was significantly developed during HA, as evidenced by end-exercise Tre (DAY1 vs. 5) (38.89+/-0.56 vs. 38.66+/-0.44 degrees C), Tsk (38.07+/-0.51 vs. 37.66+/-0.48 degrees C), HR (175.0+/-9.9 vs. 165.0+/-18.5 beatsmin-1), and sweat rate (1.24 +/-.26 vs. 1.47 +/-0.27 L ·min-1) (P<0.05). However, there was no significant difference in either LA. concentrations (LA0min: 8.78+/-1.08 vs. 8.69+/-1.23; LApeak: 10.97+/-1.77 vs. 10.95+/-1.46; and La60min; 2.88+/-0.82 vs. 2.96+/-0.93 mmol·L-1) or removal kinetics (A2: -13.05+/-7.05 vs -15.59+/-7.90 mmol.L-1 and y2:0.02+/-0.01 vs. 0.03+/-.01 min-1). CONCLUSIONS: The present study concluded that, while effective in inducing thermo-physiological adaptations to heat stress, short-term HA does not improve the body's ability to remove LA following maximal exercise. Therefore, athletes and workers seeking faster LA recovery from intense physical activity may not benefit from short-term HA. [Description provided by NIOSH]
• Subjects:
  Aging Heat Stress Disorders Hematologic Tests Hot Temperature Men Occupational Health Safety Staff Development
• Keywords:
  Adaptation Age-groups Author Keywords: Acidosis Blood-sampling Exercise Test Heat Heat-exposure Heat-regulation Heat-tolerance Heat Stress Heat Stress Disorders Humans Lactic Physical-exercise Physical-reactions Physiological Physiological-effects Physiological-function Physiology Training

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• ISSN:
  0022-4707
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  NPPTL - National Personal Protective Technology Laboratory
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  70-78
• Volume:
  56
• Issue:
  1
• NIOSHTIC Number:
  nn:20047970
• Citation:
  J Sports Med Phys Fitness 2016 Jan-Feb; 56(1):70-78
• Contact Point Address:
  Jung-Hyun Kim, PO Box 18070, Pittsburgh, PA, USA 15236
• Email:
  inr3@cdc.gov
• CAS Registry Number:
  Oxygen (CAS RN 7782-44-7)
• Federal Fiscal Year:
  2016
• Peer Reviewed:
  True
• Source Full Name:
  The Journal of Sports Medicine and Physical Fitness
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:600df5ccbf8a48181fb255395ae0da934a7436717c6e247434faa4d622fa8ce2add633c5397e50724a8ff66499f3472e10834c7bab779b3304f3c0a35f59d077
• Download URL:
  https://stacks.cdc.gov/view/cdc/202882/cdc_202882_DS1.pdf
• File Type:
  [PDF - 6.14 MB ]