The study of genetic influence in the making of an Olympic champion is still in its nascence, but recent work has provided findings regarding the association of the ACTN3 gene on athletic performance. The aim of this study was to examine genetic differences among elite Greek track and field athletes by analysing a mononucleotide polymorphism in exon 15 of the ACTN3 gene. Results showed that ACTN3 genotype and allele frequencies in the top power-oriented athletes were statistically significantly different from those in a representative random sample of the Greek population: the frequency of the RR ACTN3 genotype in power-oriented athletes vs. the general population was 47.94 % vs. 25.97 %. This result was even more prominent for comparison of the subgroup of sprinters to controls. The results suggest an overall strong association between the presence of the RR genotype and elite power performance.

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The additional use of a diode laser in the surgical treatment of peri-implantitis offers a limited clinical benefit.

Inflammatory responses and muscle damage indices were compared between four popular team sports at an elite level. Seventy two male elite players of four team sports: soccer (n = 18), basketball (n = 18), volleyball (n = 18) and handball (n = 18), completed an official match, while 18 non-athletes served as controls. Blood samples were drawn before, immediately after and 13 and 37 h post-match. Soccer produced the greatest increase in inflammatory cytokines (tumor necrosis factor-alpha and interleukin-6), which were increased by 3-4 fold immediately after the game, as well as in C-reactive protein, which was increased by threefold in the next morning after the match. Metabolic stress (urea, ammonia and cortisol) and muscle damage indices (creatine kinase and lactate dehydrogenase) were also higher after soccer, with creatine kinase responses being almost 2-3 times higher than the other sports. Volleyball showed the smallest increase in inflammation and muscle damage markers compared with the other three sports.

The aim of this study was to examine the effect of a soccer (strength and technique) training program on kinematics and electromyographic (EMG) muscle activity during a instep kick. Ten amateur soccer players (aged 19.9 AE 0.4 years, body mass 74.8 AE 9.1 kg, height 177.4 AE 6.7 cm) constituted the experimental group (EG) whereas 10 players (age 21.6 AE 1.3 years, weight 71.5 AE 6.7 kg, height 175.2 AE 3.4 cm) served as controls (CG). The EG followed a 10-week soccer-specific training program combining strength and technique exercises. All participants performed an instep soccer kick using a two-step approach while threedimensional data and EMG from six muscles of swinging and support legs were recorded prior to and after training. Maximum isometric leg press strength, 10-m sprint performance and maximum speed performance on a bicycle ergometer were also measured. Analysis of variance designs with repeated measures showed that the EG improved significantly (Po0.05) maximum ball speed, the linear velocity of the foot, ankle and angular velocity of all joints during the final phase of the kick. Training had insignificant effects on EMG values, apart from an increase in the averaged EMG of the vastus medialis whereas maximum isometric strength and sprint times significantly improved after training (Po0.05). The present results suggest that the application of the training programs using soccer-specific strength exercises would be particularly effective in improving of soccer kick performance.