The maximal aerobic performance (V02 max) and energy costs of cycling at various power outputs and equivalent road speeds of a highly trained endurance cyclist (age 23.4 yrs, height 1.95 m, weight 73.1 kg), were measured in the laboratory on an eddy-current cycle ergometer, and the physiological responses related to determinations made during a 24 h cycling time trial event, using continuous ECG recording from which estimates of ergogenic demands were obtained.The cyclist covered a distance of 694 km during the event at an average speed of 28.9 km.hW1 which corresponded to an equivalent oxygen cost of 38.5 ml.kgd1 min' and represented approximately 55% of his V02 max. During the event, the cyclist expended an estimated 82,680 kJ of energy, of which approximately 44,278 kJ (54%) were supplied by repeated feedings of liquids, solids and semi-solids and some 38,402 kJ (46%) came from the stored energy reserves which resulted in a 1.19 kg loss of body weight during the event. The energy demands of the activity were more than three times greater than the highest recorded values of severe industrial work, and similar to the hourly rates of expenditure of shorter duration competitive events, but above the highest values reported over other extreme endurance events over the same period of time. The results thus represent near maximal levels of sustainable ergogenic effort by man over a complete 24 h cycle.

Outcome measures need to have an acceptable level of reliability for sound use in clinical and research practice. This study compared the test-re-test reliability of four hand dynamometers measuring grip strength. Using a counterbalanced, repeated measures design, 30 healthy individuals performed three consecutive grip measurements on the MIE digital grip analyser, Baseline Bulb, Jamar® and Lafayette hand dynamometers in a random order on two separate days at the same time. Results indicated that all tools showed a similar and acceptable level of reliability, with a minimum of 90% of the repeat grip data falling within 95% of agreed levels of agreement. The dominant hand showed less variation in grip strength than the non-dominant. Hand pressure was seen to be no less reliable than hand force in a healthy population. Clinicians and researchers can be reassured that the test-re-test reliability of four commonly available dynamometers is acceptable for clinical and research work.

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