Acute Effects of Short-Term Massage Procedures on Neuromechanical Contractile Properties of Rectus Femoris Muscle.

Background and Objectives: In many sports, maintaining muscle work at an optimal level despite fatigue is crucial. Therefore, it is essential to discover the most efficient way of recovery. This study aimed to evaluate and compare the acute effects of four different recovery methods on muscle neuromechanical properties. Materials and Methods: The research was conducted using a randomized, quasi-experimental, repeated-measures design. Fourteen healthy and active male students of the Faculty of Sport and Physical Education (age 25.1 ± 3.9 years) were included in this study. The tensiomyography was used to evaluate muscle responses after four different types of short-term recovery methods (passive rest, percussive mechanical, vibro-mechanical, and manual massage) on the rectus femoris muscle on four occasions: baseline, post fatigue, post recovery and prolonged recovery. Results: The ANOVA revealed that muscle fatigue decreased maximal vertical muscle displacement (Dm) and muscle contraction time (Tc) in post fatigue compared to the baseline. The most important finding shows that only the vibro-mechanical massage resulted in an increase in Tc in the prolonged recovery compared to the post fatigue (p = 0.028), whereas only manual massage showed no differences in Dm from the baseline in post-recovery (p = 0.148). Moreover, both manual and vibro-mechanical massages increased Dm and Tc in prolonged recovery, indicating no differences from the baseline (all p > 0.05), thus showing signs of muscle recovery. Percussion mechanical massage and passive rest did not show indices of muscle recovery. Conclusions: Manual massage could induce immediate positive changes in Dm by reducing muscle stiffness. In addition, vibro-mechanical and manual massage improved muscle tissue by rapidly returning Dm and Tc values to baseline at prolonged recovery measurement (5 min after the fatigue protocol). These findings can benefit sports practitioners, and physical therapists in developing the best recovery method after muscle fatigue.

Bone health among indoor female athletes and associated factors; a cross-sectional study.

This study aimed to compare the bone-mineral-density (BMD), vitamin-D (25(OH)D), serum-calcium and serum-phosphorus levels between female athletes engaged in weight-bearing and non-weight-bearing-sport, and to evaluate possible associations among studied variables. Study involved top-level female athletes (age: 16.9 ± 4.4 years) involved in non-weight-bearing- (swimming; n = 14)), and weight-bearing-sport (artistic gymnastic; n = 17). The variables included the BMD of left femoral neck (measured by dual-energy X-ray absorptiometry), 25-hydroxyvitamin D levels (25(OH)D), body height, body mass, body-mass-index, serum-phosphorus, and serum-calcium levels. Sufficiency for 25(OH)D (>75 nmol/L) was observed in 32.3% of the studied athletes (43% and 23% for swimmers and gymnasts, respectively). The studied athletes had appropriate BMD, with higher BMD in gymnasts compared to swimmers (1.24 ± 0.11 and 0.85 ± 0.09 g/cm2; t-test: 10.26, p < 0.01). Serum-phosphorus was higher in gymnasts (1.46 ± 0.17 and 1.27 ± 1.36 mmol/L, t-test: 2.78, p < 0.01. Serum-phosphorus levels were lower in athletes with 25(OH)D sufficiency (t-test: 2.31, p = 0.03). The 25(OH)D was not correlated to BMD (Pearson's r = -0.18, -0.14, -0.28, all p > 0.05, for total sample, gymnasts and swimmers, respectively). Although 25(OH)D was not correlated with BMD, in further investigations other assays of vitamin-D status (i.e. the bioavailability of the vitamin-D) should be included.