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Abstract:    The aim of this study was to ascertain the effect of a six week plyometric training
 program on the RE and 3000 meter time of a group university of middle distance
 athletes. Eight club level middle distance university athletes completed a twelve
 minute sub maximal test on a treadmill and a 3000 meter maximum effort run. The
 treadmill test was completed at velocities of 12, 14 and 16kmph (each for four
 minutes). Oxygen uptake was recorded and their running economy was calculated
 for each velocity. The 3000 meter run took place on a 400 meter outdoor running
 track. Four of the participants (experimental group) then completed a six week
 plyometric training program alongside their usual training while the remaining four
 (control group) carried on with their normal training. After the six weeks all
 participants repeated the tests. A paired t-test was conducted on the results and it
 was found that the plyometric training only had a significant effect on the RE of the
 participants who completed the training at 12kmph (p=0.004) and had no effect at all
 on their 3000 meter time. It was found that six weeks of plyometric training had no
 significant effect on the RE or 3000 meter time of middle distance athletes.

We are all familiar with the negative effects of a diet high in salt — from increased risk of cardiovascular dis-ease to worsening of autoimmune disease — so why have humans evolved to store high levels of salt in the body, particularly in the skin? New evidence points to a role for salt in contributing to cutaneous anti bacterial  defences.

Abstract
Abstract: Huovinen, HT, Hulmi, JJ, Isolehto, J, Kyröläinen, H, Puurtinen, R, Karila, T, Mackala, K, and Mero, AA. Body composition and power performance improved after weight reduction in male athletes without hampering hormonal balance. J Strength Cond Res 29(1): 29–36, 2015—The aim of this study was to investigate the effects of a 4-week weight reduction period with high protein and reduced carbohydrate intake on body composition, explosive power, speed, serum hormones, and acid-base balance in male track and field jumpers and sprinters. Eight participants were assigned to a high weight reduction group (HWR; energy restriction 750 kcal·d−1) and 7 to a low weight reduction group (LWR; energy restriction 300 kcal·d−1). Energy and carbohydrate intake decreased significantly (p ≤ 0.05) only in HWR by 740 ± 330 kcal·d−1 and 130 ± 29 g·d−1, respectively. Furthermore, total body mass and fat mass decreased (p ≤ 0.05) only in HWR by 2.2 ± 1.0 kg and 1.7 ± 1.6 kg, respectively. Fat-free mass (FFM), serum testosterone, cortisol, and sex hormone–binding globulin did not change significantly. Ca2+ ion and pH decreased (p ≤ 0.05) only in HWR (3.1 ± 2.8% and 0.8 ± 0.8%, respectively), whereas

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declined (p ≤ 0.05) in both groups by 19.3 ± 6.2% in HWR and by 13.1 ± 8.5% in LWR. The countermovement jump and 20-m sprint time improved consistently (p ≤ 0.05) only in HWR, by 2.6 ± 2.5 cm and 0.04 ± 0.04 seconds, respectively. Finally, athletes with a fat percentage of 10% or more at the baseline were able to preserve FFM. In conclusion, altered acid-base balance but improved weight-bearing power performance was observed without negative consequences on serum hormones and FFM after a 4-week weight reduction of 0.5 kg·wk−1 achieved by reduced carbohydrate but maintained high protein intake.

Abstract: Ćopić, N, Dopsaj, M, Ivanović, J, Nešić, G, and Jarić, S. Body composition and muscle strength predictors of jumping performance: Differences between elite female volleyball competitors and nontrained individuals. J Strength Cond Res 28(10): 2709–2716, 2014—Studies of the role of various anthropometric, physiological, and biomechanical variables in performance of rapid movements have generally revealed inconsistent findings. Within this study, we tested the hypotheses that (a) both body composition and leg extensor strength variables would reveal significant relationship with jumping performance, whereas (b) the same relationships would be stronger in physically active nonathletes than in the elite athletes proficient in vertical jumping. Top-level female volleyball players (VP; N = 35) and physically active female nonathletes (PA; N = 21) were tested on maximum vertical jumps performed with and without arm swing, as well as on body composition (percent fat and muscle) and leg press strength (maximum force and the rate of force development). The results revealed significant relationships between the jumping performance and body composition variables that appeared to be higher in PA (r = 0.65–0.76; all p < 0.01) than in VP (r = 0.37–0.42; all p ≤ 0.05). The relationships between the jumping performance and the leg strength variables were mainly significant (r = 0.23–0.68) and similar in 2 groups. We conclude that not only the leg extensor strength but also the body composition variables could be valid predictors of jumping performance and, possibly, other rapid movements. Moreover, the body composition variables that have been mainly neglected in the literature could be particularly strong predictors of performance of jumping in nonathletes, as compared with relatively homogeneous populations of elite athletes.