Keiji Yamaji

Influence of running pace upon performance: effects upon treadmill endurance time and oxygen cost.

SummaryThree possible patterns of pacing (type 1, fast/slow; type 2, slow/fast; and type 3, steady rate) were compared over a 1400 m, 4 min run. The subsequent running time to exhaustion at 370 m·min−1 was significantly longer with a type 1 than with a type 2 protocol (P<0.05). The steady rate pattern gave results intermediate between type 1 and type 2 pacing. Data for oxygen debt and recovery heart rate confirmed the superiority of type 1 pacing. Possible explanations included (1) a reduction of inefficient anaerobic work, and (2) a greater mechanical efficiency associated with the better matching of required effort to a tapering physiological power. Runners should aim at a steady physiological rather than a steady physical load.

Differences in cardio-respiratory responses to exhaustive exercise between athletes and non-athletes

SummaryTo study the factors limiting the O2 supply in heavy exercise, O2 uptake at exhaustion was determined by progressive loading method with a bicycle ergometer in 33 well-trained male runners and 34 male sedentary adults. Pulmonary ventilation, oxygen removal, respiratory rate, tidal volume, pulmonary diffusing capacity, alveolar-capillary oxygen difference, cardiac output, arterial-venous oxygen difference, stroke volume and heart rate were measured. It was found that pulmonary diffusing capacity, cardiac output and stroke volume were correlated with the difference in O2 uptake at exhaustion between athletes and non-athletes.

Oxygen transport system during exhaustive exercise in Japanese boys.

SummaryThe study was designed to investigate the age-related increase in maximal oxygen uptake with special reference to the other physiological parameters (ventilation, pulmonary diffusing capacity, cardiac output etc.). 77 normal boys aged 10–18 years were tested by the progressive loading method on a bicycle ergometer.

RELATIONSHIP BETWEEN HEART RATE AND RELATIVE OXYGEN INTAKE IN MALE SUBJECTS AGED 10 TO 27 YEARS

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Biological rhythms of PWC170 and maximal oxygen intake.

O2 max increased by approximately 55% with age from 10–18 years. The increase in

Pulmonary Diffusing Capacity as a Factor of Aerobic Work Capacity

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