There is a limit to the performance of an organism set by energy intake and energy mobilization. Here, the focus is on humans with unlimited access to food and for whom physical activity can be limited by energy mobilization. The physical activity level (PAL) in the general population, calculated as doubly-labelled-water-assessed average daily metabolic rate as a multiple of basal metabolic rat...

Correspondence to Dr Christian Schmied; [email protected] ‘All things are poison and nothing is without poison, only the dose makes a thing not a poison’. When Phillipus Aureolus Theofrastus Bombastus von Hohenheim—better known as ‘Paracelsus’—a Swiss German Renaissance physician, botanist, astrologer and philosopher coined this well-known quote about 500 years ago, he might not have tho...

This project examined the feasibility, validity, and reliability of the plank isometric hold for children 8-12 years of age. 1502 children (52.5% female) performed partial curl-up and/or plank protocols to assess plank feasibility (n = 823, 52.1% girls), validity (n = 641, 54.1% girls) and reliability (n = 111, 47.8% girls). 12% (n = 52/431) of children could not perform a partial curl-up, but ...

Trade-offs are thought to impose barriers to phenotypic diversification and may limit the evolutionary responses of organisms to environmental changes. In particular, locomotor trade-offs between endurance or maximal exertion capacity and burst performance capacity have been observed in some species and may constrain the ability of organisms to disperse. Here, we tested for the presence of loco...

AIMS We assessed the changes in cardiac morphology between elite endurance-trained runners (n = 42) and elite sprinters (n = 34) over a 5-year period. In addition, we studied the relationship between heart size and maximum oxygen consumption (VO2 max). METHODS At the beginning of 5 consecutive seasons, all athletes underwent an incremental running test to determine VO2 max and a color-coded p...

In the exercising human, maximal oxygen uptake (VO2max) is limited by the ability of the cardiorespiratory system to deliver oxygen to the exercising muscles. This is shown by three major lines of evidence: 1) when oxygen delivery is altered (by blood doping, hypoxia, or beta-blockade), VO2max changes accordingly; 2) the increase in VO2max with training results primarily from an increase in max...

We analyse the development of world records speed skating from 1893 to 2000 for both men and women. The historical data show that it is likely that the relation between skating speed and distance of the various events is non-linear and converges to a limit value. We pay special attention to technical innovations in speed skating, especially, the introduction of the klapskate in the 1996/1997 se...

To determine helicopter component retirement intervals, it is common for fatigue engineers to utilize Miner’s rule for cumulative damage. Time consuming Monte Carlo simulations are considered the state of the art method for determining reliability in the presence of load variations. However, a new set of methods employed on a recent AHS fatigue reliability round robin problem provide an indicat...