Acute physiological responses in healthy men during whole-body vibration
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Objective: The influence of backrest support and handgrip contractions on acute metabolic, respiratory, and cardiovascular responses were evaluated in 13 healthy men during exposure to whole-body vibration (WBV). Methods: Following assessment of aerobic fitness during arm cranking, subjects were exposed to frequencies 3, 4.5, and 6 Hz with 0.9 gr.m.s acceleration magnitude on a vibrating base in randomized order, on separate days. Each exposure included 6 min baseline without WBV, 8 min of WBV exposure either ‘with‘ or ‘without’ backrest, 4 min recovery, followed by 8 min of WBV with opposite backrest condition, and 4 min recovery. During the final minute of WBV, subjects performed right hand maximal rhythmic handgrip contractions for one minute. During baseline and before completion of WBV session ‘with’ and ‘without’ backrest, cardiac output was estimated indirectly by carbon dioxide rebreathing. Results: At 3 and 4.5, and 3 and 6 Hz, absolute and relative oxygen uptake demonstrated significantly greater responses during sitting ‘without’ backrest than ‘with’ backrest (P<0.01). At 3 and 4.5 Hz, heart rate and oxygen pulse responses were significantly greater during WBV combined with handgrip contractions than during WBV alone (P<0.01), demonstrating physical work during WBV will enhance greater metabolic responses. Stroke volume was the lowest at 4.5 Hz (P<0.01). Influence of aerobic fitness was evident only in absolute oxygen uptake, oxygen pulse, and ventilation volume (P<0.01). Conclusions: This study demonstrates that subjects exposed to physical work during WBV will experience greater metabolic responses compared to WBV alone, and the physiological responses during WBV resemble to that of a light physical work. Despite low metabolic rates during WBV, the effect of aerobic fitness suggests the importance of physical activity in occupations exposed to WBV.
KeywordsCardiorespiratory responses Handgrip contractions Backrest support Spinal resonance frequency Aerobic fitness
This study was part of the doctoral dissertation done by the first author at the University of Alberta, Edmonton, Canada. This project was partly supported by the Small Faculties Grant, University of Alberta, Edmonton, Canada. The authors sincerely thank Al Fleming and Brian Henderson for their technical assistance, and Martha Roxburgh and Sharon Brintell of the Occupational Analysis Performance Unit for loaning the Vibrating Simulator. We are also grateful to Gurpreet Sidhu, Winnie Ting, Geetanjali Kashyap, and Mamdouh Farag for their help in initial experimental setup and data collection. All of the experiments conducted complied with the current laws of Canada.
- Andersson GBJ, Chaffin DB, Pope MH (1991) Occupational biomechanics of the lumbar spine. In: Pope MH, Andersson GBJ, Frymoyer JW, Chaffin DB (eds) Occupational low back pain. Assessment, treatment, and prevention. Mosby Year Book, Chicago, pp 20–43Google Scholar
- Bennett MD, Webb R, Withey WR (1977) Personality, performance and physiological cost during vibration. Proc Physiol Soc 270(1):75–76Google Scholar
- Boff KR, Lincoln JE(1988) Vibration and display perception. In: Engineering data compendium: human perception and performance. AAMRL, Wright-Patterson Air Force Base, OH, pp 2064–2066Google Scholar
- Borg G (1982) Psychophysical bases of perceived exertion. Med Sci Sports Exerc 29:402–409Google Scholar
- Griffin MJ (1990) Vibration and discomfort. In: Handbook of human vibration. Academic, New York, pp 43–123Google Scholar
- Guinard JC (1985) Vibration. Chapter 15. In: Patty’s industrial hygiene and toxicology. vol. 3b: biological responses. Wiley, New YorkGoogle Scholar
- Jones NL (1986) Clinical exercise testing. Saunders, Toronto, pp 193–194Google Scholar
- McArdle WD, Katch I, Katch VL (1996) Exercise physiology. Williams & Wilkins, Baltimore, pp 159Google Scholar
- Panjabi MM, Andersson GBJ, Jorneus L, Hult E, Mattsson L (1986) In vivo measurement of spinal column vibrations. J Bone Joint Surg 68A(5):695–703Google Scholar
- Pope MH, Magnusson M, Lindell V, Svensson M, Andersson GBJ (1990). The measurement of oxygen uptake under whole-body vibration. Iowa Orthop J 10:85–88Google Scholar
- Thornton R, Brown GA, Higenbottam C (1984) The energy expenditure of helicopter pilots. Avi Space Envi Med 55:746–750Google Scholar