TY - JOUR
T1 - Determining an optimal recovery time after exercising to exhaustion in a controlled climatic environment
T2 - Application to construction works
AU - Chan, Albert P.C.
AU - Wong, Francis K.W.
AU - Wong, Del P.
AU - Lam, Edmond W.M.
AU - Yi, Wen
N1 - Funding Information:
This project is funded by a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (RGC Project No. PolyU510409 ). The support from the Hong Kong Polytechnic University's Institute of Textiles and Clothing (ITC) is deeply appreciated. The research team is also indebted to the technical support from technicians of the Hong Kong Polytechnic University and the Hong Kong Institute of Education. In particular, the participation of volunteers in this experimental study is gratefully acknowledged. This paper forms part of the research project titled “Experimental research on health and safety measures for working in hot weather”, from which other deliverables will be produced with different objectives/scopes but sharing common background and methodology. The authors also wish to acknowledge the contributions of other team members including Dr Michael Yam, Dr Daniel Chan, Prof Joanne Chung, Prof Esmond Mok, Dr Geoffrey Shea, Dr Min Wu, Dr Herbert Biggs, Dr Donald Dingsdag, and Miss Alice Guan.
PY - 2012/10
Y1 - 2012/10
N2 - This study aims to determine an optimal recovery time after a participant has exercised to exhaustion in a controlled climatic condition. Ten males and four females volunteers were examined under hot (30°C) and humid (75% relative humidity) environment in a climatic chamber to simulate typical summer outdoor working conditions of construction workers in Hong Kong. The participants (age 31.3 ± 9.3 years; height 168.5 ± 9.8 cm; weight 62.5 ± 7.1 kg; and percentage body fat 22.9 ± 7.2%) performed graded upper body exercise at a target cadence of 70 rotation per minute (RPM) until exhaustion and were recovered inside the climatic chamber until their physiological conditions returned to the pre-exercise level or lower. Physiological Strain Index (PSI) was used as a yardstick to determine the rate of recovery. The physiological conditions of the participants were monitored by recording their ear temperature (to estimate core temperature), heart rate, oxygen consumption, respiratory exchange ratio and Ratings of Perceived Exertion (RPE). It was found that on average a participant could achieve 97% energetic recovery in 40 min; 90% in 35 min; 82% in 30 min; 75% in 25 min; 68% in 20 min; 60% in 15 min; 53% in 10 min; and 46% in 5 min. Linear regression results showed that recovery time is a significant independent variable to determine the rate of recovery (R2 = 0.95, P < 0.05). Depending on the level of recovery, an optimal recovery time after exhaustion in a hot and humid environment can be determined based on these findings.
AB - This study aims to determine an optimal recovery time after a participant has exercised to exhaustion in a controlled climatic condition. Ten males and four females volunteers were examined under hot (30°C) and humid (75% relative humidity) environment in a climatic chamber to simulate typical summer outdoor working conditions of construction workers in Hong Kong. The participants (age 31.3 ± 9.3 years; height 168.5 ± 9.8 cm; weight 62.5 ± 7.1 kg; and percentage body fat 22.9 ± 7.2%) performed graded upper body exercise at a target cadence of 70 rotation per minute (RPM) until exhaustion and were recovered inside the climatic chamber until their physiological conditions returned to the pre-exercise level or lower. Physiological Strain Index (PSI) was used as a yardstick to determine the rate of recovery. The physiological conditions of the participants were monitored by recording their ear temperature (to estimate core temperature), heart rate, oxygen consumption, respiratory exchange ratio and Ratings of Perceived Exertion (RPE). It was found that on average a participant could achieve 97% energetic recovery in 40 min; 90% in 35 min; 82% in 30 min; 75% in 25 min; 68% in 20 min; 60% in 15 min; 53% in 10 min; and 46% in 5 min. Linear regression results showed that recovery time is a significant independent variable to determine the rate of recovery (R2 = 0.95, P < 0.05). Depending on the level of recovery, an optimal recovery time after exhaustion in a hot and humid environment can be determined based on these findings.
KW - Hot and humid environment
KW - Optimal recovery time
KW - Physiological parameters
KW - Physiological strain index (PSI)
KW - Ratings of perceived exertion (RPE)
UR - http://www.scopus.com/inward/record.url?scp=84858744209&partnerID=8YFLogxK
U2 - 10.1016/j.buildenv.2012.02.013
DO - 10.1016/j.buildenv.2012.02.013
M3 - Journal article
AN - SCOPUS:84858744209
VL - 56
SP - 28
EP - 37
JO - Building and Environment
JF - Building and Environment
SN - 0360-1323
ER -