The article Swimming as Treatment for Osteoporosis: A Systematic Review and Meta-analysis by Journal of biomedicine and biotechnology gave important answers regarding swimming and osteoporosis. Here we can read the interesting abstract of the article: "Osteoporosis is a chronic disease that seriously affects human health and quality of life.
This study is aimed at determining whether swimming had an effect on the bone mineral density (BMD) of the spine and femoral neck in postmenopausal and premenopausal osteoporosis patients. We retrieved relevant literature and analyzed data from randomized controlled trials to assess the effect of swimming on BMD in postmenopausal and premenopausal women.
Relevant studies, with no language restrictions, from inception to September 2019, were retrieved from the PubMed, Cochrane, EMBASE, and EBSCO databases independently by two investigators. The keywords used for the literature search were "osteoporosis" and "swimming."
The main results included BMD and T-score. We searched 256 relevant articles and finally screened five articles, including 263 participants. Lumbar spine density was mentioned in three articles. Although the heterogeneity of lumbar vertebral density is moderate, the analysis of swi mmers to nonswimmers shows that the lumbar vertebral density in swimmers is improved [heterogeneity: chi2 = 5.16, df = 2 (P = 0.08); I 2 = 61%].
We analyzed the following heterogeneous subgroups: subgroup 1 (3-6 hours) and subgroup 2 (<3 hours). The BMD in subgroup 1 was significantly higher than that in the placebo, while no effect on BMD was found in subgroup 2 [heterogeneity: chi2 = 0.15, df = 3 (P = 0.70); I 2 = 0%].
According to the current evidence, swimming may improve the BMD of postmenopausal women participants, if the swimming time is between 3 and 6 hours, especially in long-term swimmers. However, the effectiveness of swimming does require further investigation."
Change-of-direction, speed and jump performance in soccer players
Change-of-direction, speed and jump performance in soccer players: a comparison across different age-categories is a 2019 study that gives very interesting results on these correlations that influence the performances of the soccer player, and published on the Journal of sports sciences.
Below you can read an abstract: "This study examined the age-specific development of vertical jump height, straight and change-of-direction (COD) speed, and COD deficit in one-hundred and eighty-two elite soccer players from different age-categories (U15, U17, U20, and Senior).
All participants were players of two distinct clubs and were undertaking different training routines, as planned by their technical staff members. For this purpose, the soccer players performed: (1) squat and countermovement jumps; (2) a maximal 20-m linear sprint speed test, and (3) the Zigzag COD test.
T he magnitude-based inference approach and standardized differences were used to compare the age-groups. Sprint speed at longer distances (20-m) increased progressively across the age-ranges. In contrast, speed and acceleration performances at shorter distances (5-m) were better in U15 than in the other age-categories.
The COD speed did not change throughout the younger categories but presented a meaningful decrease in the Senior category. Sur prisingly, despite the progressive increase in volume and intensity of neuromuscular training from younger to older categories, the COD deficit presented a gradual increase across the age-groups.
It is possible that simple modulation of the strength-power training program during the maturation process is not sufficient to produce faster adult players with enhanced ability to change direction. Therefore, coaches are strongly encouraged to implement specific COD training practices to tolerate braking at increasing running speeds and appropriate volume and intensity of soccer specific training throughout the players' specialization process."