| Summary: | Acknowledging the specificity of assessing maximal output, the purpose of this paper was to compare the physiological and perceptual responses during a traditional running activity and the common industrial task of lifting; both were taken to maximal effort. The responses of eight male participants were measured during both physical activities separated by at least five days: i) a progressive speed protocol (PSP) involved running on a treadmill at increasing speeds, starting at 10 km.h[superscript -1] and increasing by 1 km.h[superscript -1] every minute until exhaustion; ii) a progressive frequency protocol (PFP) required participants to lift a load of 20% body mass at increasing lifting frequencies, starting at one lift every 10s and reducing the time between lifts by 1s every minute until exhaustion. Physiological responses were measured using a portable on-line system, the K4b[superscript 2] (Cosmed(r)). "Central" perceptual measures were obtained every minute using the rating of perceived exertion (RPE) scale. Results: Responses increased progressively with augmented exercise intensity in both protocols; however, oxygen consumption and peak oxygen values were both lower during the lifting protocol compared to the running protocol. In contrast to the oxygen uptake responses, peak RER values were significantly higher during lifting (mean of 1.32) than running (mean of 1.18), while maximal heart rate and perceptual responses revealed no significant difference between the two protocols. These findings caution against using the 'traditional' treadmill protocol to assess the aerobic capacity of manual labourers involved in lifting, as it is evident that the traditional lower body protocol will indicate a higher capacity than the maximum capacity of an upper body activity, which could lead to manual labourers being taxed beyond acceptable limits.
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