On 6 healthy adult males aged 20-30 years, oxygen pulse was observed during carrying sand bags weighing 10, 20 and 30 kg on a level treadmill running with speeds of 3, 4 and 5 km/hr. The results obtained were as follows.
1. Oxygen pulse during load carrying on a level treadmill was proportionately increased with an increase -of work I oad, average oxygen uptake per minute. Regression equation of oxygen pulse (y: mlJbeat) on the average oxygen uptake (z: Z/min) required for each grade of work was expressed as y=3.34 x-´5.99, s,..= =0.858).
2. Oxygen pulse reached the highest value 2-5 minutes after the start of load carrying, and thereafter it decreased gradually to some extend as the load carrying was continued. Rate of decrease in the oxygen pulse was greater in lighter works.
3. In lighter works requiring less than 2.0 Z/min of oxygen uptake, no difference in oxygen pulse could be seen between methods of carrying even when the same amount of load was carried. In heavier works requiring more than 2.0 Z/min of oxygen uptake, oxygen pulse was larger in case of carrying a load by embrace, in both hands and on head than in back or on shoulder
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