The differences in cardiorespiratory responses were examined during and after intermittent progressive maximal arm-crank and cycle exercise. Arm-crank exercise was performed in a standing position using no torso restraints to maximize the amount of active skeletal muscle mass. Recovery was followed for 16 min. In the tests a variety of ventilatory gas exchange variables, heart rate, the blood pressure, and the arm venous blood lactate concentration were measured in 21 untrained healthy men aged 24-45 years. At equal submaximal external workloads for arm cranking and cycling (50 and 100 W) the respiratory frequency, tidal volume, pulmonary ventilation, oxygen uptake, carbon dioxide output, the respiratory exchange ratio, heart rate, the arm venous blood lactate concentration, and the ventilatory equivalent for oxygen were higher (P less than 0.001) during arm cranking than cycling. The maximal workload for arm cranking was 44% lower than that for cycling (155 +/- 37 vs 277 +/- 39 W, P less than 0.001) associated with significantly (P less than 0.001) lower maximal tidal volume (-20%), oxygen uptake (-22%), carbon dioxide output (-28%), systolic blood pressure (-17%) and oxygen pulse (-22%) but a higher ventilatory equivalent for carbon dioxide (+22%) and arm venous blood lactate concentration (+37%). However, these responses after arm-crank and cycle exercises behaved almost similarly during recovery. The high cardiorespiratory stress induced by arm work should be taken into account when the work stress and work-rest regimens in actual manual tasks are assessed, and when arm work is used for clinical testing, and in physiotherapy particularly for patients with heart or pulmonary diseases.

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Physiological responses including ventilatory gas exchange, blood lactate (LA) and heart rate (HR) were studied during and after intermittent manual sorting of postal parcels in a simulated workplace constructed in the laboratory. Responses to parcel sorting were compared to those obtained during arm crank and cycle exercise. The subjects were 21 healthy male sorters. Their age was 33 * 6 years and weight 78.3 f 12.7 kg. The subjects' maximal oxygen consumption (VO, max) was 2-52 f 0.32 I min ' for arm cranking, and 3.24+_044 1 min -' for cycling. The subjects sorted parcels with a mean weight of 5.1 kg from a container onto two trollies for 3.5 min at each of the following work rates: slow (3 + 0 parcels mine I), habitual (8-6 f 2.4 parcels min-I), accelerated (10-8 + 3.1 parcels min-I), and maximal (16.9f 7-6 parcelsmin-I). The tasks were separated by rest periods of 30 s for venous blood sampling, and the recovery was followed for 16 min. At the habitual work rate, P O 2 was 1-36 f 0.38 1 min-', LA 1-8 f 0.9 mmol 1-', and HR 105 & 22 beats min ' . The parcel sorting studied was predominantly aerobic (LA < 4-0 mmol 1 -') up to the work rate of about 20 parcels min-I . After the recovery period, breathing frequency and HR remained significantly higher than at rest. The physiological responses to parcel sorting substantially differed from those to arm cranking, whereas they were almost equal to cycling.

An exercise program to prevent coronary heart disease in middle-aged men is described and its effects on the subjects' physical fitness are reported. MethodsA feasibility study on physical activity intervention for coronary heart disease prevention among middle-aged sedentary men displaying relatively high values in selected coronary heart disease (CHD) "risk factors" has been performed in Helsinki, Finland. CHD risk status, clinical contraindications, motivation, and habitual physical activity were the criteria used for selecting the subjects. Half of the group was subjected to a relatively vigorous physical training program which lasted 18 months, while the other half was used as a control group. This paper reports on the training program utilized in the intervention study. It describes the organization, administration, and content of the program, the adherence and rate of participation of the subjects, injuries caused by the training, the subjects' evaluation of the program, and effects of training on selected physical fitness variables. Effects on other variables will be published elsewhere.

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