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This article examines the effects of muscle damage from a session of maximal eccentric exercise on muscle strength gains during subsequent physical training. Findings indicate that exercise-induced muscle damage compromised strength directly following the session and did not result in increased gains in muscle strength after the nine-week training protocol.

A study compares the neuromuscular performance of explosive power athletes, determined by electromechanical delay (EMD) and rate of force development (RFD), with that of untrained individuals. Findings indicate that explosive power athletes have a greater normalized RFD and neural activation in the initial duration of neuromuscular performance than untrained individuals.

The study establishes the optimal crank length and crank-axle height for maximum power production during standing arm cranking ('grinding'). Results indicate changes in crank length and crank-axle height influence performance during grinding, indicating that standard leg-cycle crank lengths are unsuitable for maximal arm-cranking performance.

A study was conducted to ascertain the connection between salivary immunoglobulin A (s-igA) and upper respiratory infections (URI) in professional athletes over a long period. Results revealed that a high s-IgA indicated an incidence of URI and this could periods of susceptibility.

A study has assessed the relationship between circulating angiotensin-1 converting enzyme (ACE) activity, strength or the gain in strength in response to training. Conclusions reveal that the data support a role for ACE in the regulation of human skeletal muscle strength however does not confirm a role in altering the response to short-term training.

Whilst extensive research has detailed the loss of muscle strength with ageing for isolated single joint actions, there has been little attention to power production during more functionally relevant multiple joint movements. The extent to which force or velocity are responsible for the loss in power with ageing is also equivocal. The aim of this study was to evaluate the contribution of force and velocity to the differences in power with age by comparing the force–velocity and power–velocity relationships in young and older men during a multiple joint leg press movement.Twenty-one older men (66 ± 3 years) and twenty-three young men (24 ± 2 years) completed a series of isometric (maximum and explosive) and dynamic contractions on a leg press dynamometer instrumented to record force and displacement.The force–velocity relationship was lower for the older men as reflected by their 19 % lower maximum isometric strength (p< 0.001). Explosive isometric strength (peak rate of force development) was 21 % lower for the older men (p< 0.05) but was similar between groups when normalised to maximum strength (p= 0.58). The power–velocity relationship was lower for the older men as shown by reduced maximum power (-28 %, p< 0.001) and lower force (-20 %, p< 0.001) and velocity (-11 %, p< 0.05).Whilst force and velocity were lower in older men, the decrement in force was greater and therefore the major explanation for the attenuation of power during a functionally relevant multiple joint movement.

The response to strength training varies widely between individuals and is considerably influenced by genetic variables, which until now, have remained unidentified. The deletion (D), rather than the insertion (I), variant of the human angiotensin-converting enzyme (ACE) genotype is an important factor in the hypertrophic response of cardiac muscle to exercise and could also be involved in skeletal muscle hypertrophy - an important factor in the response to functional overload. Subjects were 33 healthy male volunteers with no experience of strength training. We examined the effect of ACE genotype upon changes in strength of quadriceps muscles in response to 9 weeks of specific strength training (isometric or dynamic). There was a significant interaction between ACE genotype and isometric training with greater strength gains shown by subjects with the D allele (mean S.E.M.: II, 9.0 1.7 %; ID, 17.6 2.2 %; DD, 14.9 1.3 %, ANOVA, P 0.05). A consistent genotype and training interaction (ID DD II) was observed across all of the strength measures, and both types of training. ACE genotype is the first genetic factor to be identified in the response of skeletal muscle to strength training. The association of the ACE I/D polymorphism with the responses of cardiac and skeletal muscle to functional overload indicates that they may share a common mechanism. These findings suggest a novel mechanism, involving the renin-angiotensin system, in the response of skeletal muscle to functional overload and may have implications for the management of conditions such as muscle wasting disorders, prolonged bed rest, ageing and rehabilitation, where muscle weakness may limit function. Experimental Physiology (2000) 85.5, 575-579.