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Swimming behind another swimmer at a distance between 0 and 50 cm back from the toes was the most advantageous, whereas in lateral drafting the optimal distance was 50-100 cm back from the hands of the lead swimmer.

Previous investigators have speculated that applying additional external load throughout the eccentric phase of the jumping movement could amplify the stretch-shortening cycle mechanism and modulate jumping performance and jump exercise intensity. The aims of this study, therefore, were to determine the effect of increased eccentric phase loading, as delivered using an elastic device, on drop jumps (DJs) performed from different drop heights. Of specific interest were changes in (a) the kinetics; eccentric and concentric impulse, rate of force development (RFD), concentric velocity and (b) the electromyographic (EMG) activity of leg muscles. In a randomized repeated-measure study, 15 highly resistance trained male subjects performed DJs from 3 heights (20, 35, and 50 cm) under 3 different conditions: body weight only (free DJ) and with elastic bands providing downward force equivalent to 20% (+20% DJ) and 30% (+30% DJ) of body mass. All DJs were recorded using video and force plate data that were synchronized with EMG data. Results demonstrated that using additional tensile load during the airborne and eccentric phases of the DJ could enhance eccentric impulse (p = 0.042) and RFD (p < 0.001) and resulted in small to moderate effect size (ES) increases in quadriceps intergrated EMG across the eccentric phase (0.23 > ES > 0.51). The observed greater eccentric loading, however, did not immediately alter concentric kinetics and jump height nor did it alter muscle activation levels during this phase. The findings indicated that, in addition to the conventional technique of increasing drop height, using a tensile load during the airborne and eccentric phases of the DJ could further improve eccentric loading of DJs. As it has been suggested that eccentric impulse and RFD are indicators of DJ exercise intensity, these findings suggest that the loaded DJs, using additional elastic load, may be an effective technique for improving DJ exercise intensity without acute effects on the jumping performance and neuromuscular activation level in highly trained athletes.

Objective: To describe the epidemiology of lower limb injuries in the New Zealand Defence Force (NZDF). Method: Data from all NZDF lower limb injury claims from an 11‐month period were examined for type, site, and circumstances of injury. Both injury codes and narratives were analysed, allowing each injury event to be classified according to mechanism of injury, object involvement, and activity at the time of injury, as well as type and site. Results: The commonest lower limb musculoskeletal injuries were ankle sprains or strains (35%) and knee sprains or strains (16%). Most commonly, injuries were due to acute over‐exertion (37%), involved no other person (50%), and occurred while running (28%) or playing team sports (25%). The injury rate for recruits was more than five times that of trained personnel. Conclusions: Potential interventions should target ankle sprains primarily, but also knee sprains and fractures. Fractures, while accounting for only 6% of lower limb injuries, should be a priority because of their high medical and time‐lost costs. Interventions must also take into account the high incidence of injuries involving individuals alone and sustained during recruit training. The study also demonstrated that analysis of military injury narratives provides valuable extra information on injury causation and the circumstances of injury, and allows more accurate characterisation of the injury process. Implications: This study will provide the basis for development of an injury prevention strategy for lower limb training injuries in the NZDF.

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