morita_2006.htm

Bulletin of Glaciological Research 23 (2006) 41-49
©Japanese Society of Snow and Ice

Differences in cardio-respiratory responses to snow shoveling
and shovel performance between elderly males and females

Isao MORITA¹, Akihiko YAMAGUCHI², and Tsutomu SUDA³
1 School of Nursing and Social Services, Health Sciences University of Hokkaido, Kanazawa, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
2 Department of Integrated Human Sciences, School of Dentistry, Health Sciences University of Kanazawa, Ishikari-Tobetsu,
Hokkaido 061-0293, Japan
3 Graduate School of Education, Hokkaido University, Sapporo, Hokkaido 060-0811, Japan

Abstract

　The purpose of this study is to elucidate the differences in cardio-respiratory responses to snow shoveling and shoveling performance between elderly males and females. Eight elderly males (EM, 61-69, mean±standard errors; 64.5±1.0 yr) and five elderly females (EF, 61-75, 67.8±2.7 yr) who are habitually engaged in manual snow removal performed 10 minutes to remove 1m width at 0.4m depth using a snow shovel. Heart rate, volume of oxygen consumption (VO₂), blood pressure, ratings of perceived exertion (RPE), and productive variables including shovel rate, shovel load and snow mass were measured. Significant differences were observed in VO₂ (1.79±0.07 vs 1.20±0.06Lmin^-1, p<0.01) and metabolic equivalent (8.2±0.5 vs 6.6±0.3 Mets, p<0.05) between EM and EF.
　Cardio-respiratory responses were somewhat higher for EM than EF, as revealed by the heart rate (158±5 vs 150±7 beatsmin^-1, ns), systolic blood pressure (183±10 vs 178±7mmHg, ns), diastolic　blood pressure (95±4 vs 84±8mmHg, ns) and RPE (14.9±0.7 vs 13.6±0.4, ns), respectively. The large　diｆｆrence in snow mass (115±18 vs 69±9 kgmin^-1, p<0.001) between EM and EF is considered to be　aｆｆected by shovel load (11.4±2.0 vs 4.9±0.2 kg, p<0.001）, not by shovel rate (10.3±2.3 vs 14.0±1.9 scoopsmin^-1, p<0.05). Volume of oxygen consumption in terms of absolute value (L・min^-1) correlated with snow mass higher (r=0.832) than relative VO₂ in terms of relative value (r=0.616).
　It was concluded that snow shoveling is strenuous exercise for the elderly and that elderly females are less productive due to their smaller body size and lower physical resources.