Resistance training (RT) has been considered an intervention with effective stimulus on bone mineral formation and is, therefore, recommended to decrease the rate of bone morpho-functional proprieties loss with aging. Thus, this meta-analysis aimed to analyze the effectiveness of RT protocols in promoting changes in bone mineral density (BMD) in older adults. The systematic reviews and meta-analysis followed the PRISMA guidelines (PROSPERO CRD42020170859). The searches were performed in the electronic databases using descriptors according to the PICO strategy. The methodological quality and risk of bias were assessed with the PEDro scale, and the magnitude of the results was determined by Hedges’ g. Seven studies involving 370 elderlies, with the RT planned as a unique exercise mode of intervention, showed designs with four to five exercises for upper- and lower-limbs musculature, two to three sets per exercise, eight to twelve repetitions to failure at 70–90% 1 RM, 60–120 s of rest between sets, and executed three times per week for 12–52 weeks. The RT protocols were classified between good and excellent and evidenced a positive effect on the BMD at the hip (0.64%) and spine (0.62%) but not in the femoral neck (−0.22%) regardless of the intervention length. The narrow range of either positive or negative changes in the BMD after the RT intervention support, at best, a preventive effect against the increasing risk of bone frailty in an older population, which is evident beyond 12 weeks of RT practice engagement.

The current study analysed whether the osteogenic stimuli of exercises and sports have an independent effect on bone mineral density (BMD). Studies with a design having two different cohorts were searched and selected to distinguish the effect due to long-term involvement (i.e., athletes vs. non-active young with good bone health) and due to the planning of intervention (i.e., pre- vs. post-training) with exercises and sports. Moreover, only studies investigating the bone sites with a body-weight support function (i.e., lower limb, hip, and spine regions) were reviewed, since the osteogenic effects have incongruous results. A meta-analysis was performed following the recommendations of PRISMA. Heterogeneity (I²) was determined by combining Cochran’s Q test with the Higgins test, with a significance level of α = 0.05. The studies reporting the effect of involvement in exercise and sports showed high heterogeneity for the lower limb, total hip, and spine (I² = 90.200%, 93.334%, and 95.168%, respectively, with p < 0.01) and the effect size on sports modalities (Hedge’s g = 1.529, 1.652, and 0.417, respectively, with p < 0.05) ranging from moderate to high. In turn, the studies reporting the effect of the intervention planning showed that there was no heterogeneity for the lower limb (I² = 0.000%, p = 0.999) and spine (I² = 77.863%, p = 0.000); however, for the hip, it was moderate (I² = 49.432%, p = 0.054), with a low effect between the pre- and post-training moments presented only for the hip and spine (Hedge’s g = 0.313 and 0.353, respectively, with p < 0.05). The current analysis supported the effect of involvement in exercise and sports by evidencing the effect of either weight-bearing or non-weight-bearing movements on BMD at the femoral, pelvic, and lumbar bones sites of the athletes when comparing to non-athletes or non-active peers with healthy bones. Moreover, the effect of different exercise and sports interventions highlighted the alterations in the BMD in the spine bone sites, mainly with long-term protocols (~12 months) planned with a stimulus with high muscle tension. Therefore, exercise and sport (mainly systematic long-term practice) have the potential to increase the BMD of bones with body-weight support beyond the healthy values reached during life phases of youth and adulthood.

Currently, there is an increase in people practicing freediving (FD) both in competition and leisure. As a sports practice, its modalities are grouped into static, dynamic, and constant weight apnea. The aim of this systematic review and meta-analysis (PROSPERO-CRD42021230322) was to identify the training methods used to improve the static apnea time (AT) performance. Ten training protocols were analyzed from eight studies published until March 09, 2022. The effect size (Hedge's g) and its confidence interval (CI95%) were calculated from the AT measured pre- and post-training. Three different apnea training methods were verified, the breath-hold (BH) that uses BH exercises, physical training with strength and cardiorespiratory exercises, and cross training that combines BH exercises with physical training. These training methods were applied to 138 participants of both sexes with or without experience in apnea episode or diving practice. In general, the AT improvement showed a large effect after the interventions (g=1.30, CI95%=0.85-1.76, P<0.01). All three methods were effective in improving static AT, however from the existing protocols is not possible to recommend an ideal to improve AT and therefore FD performance.

O ato de caminhar envolve pequenos ajustes para manutenção do equilíbrio corporal. No entanto, a demanda por estes ajustes pode ser diferente na caminhada no declive. O objetivo deste estudo foi analisar o efeito do treinamento periodizado de caminhada em declive na resposta neuromuscular dos músculos flexores do joelho. Dezessete indivíduos ativos do gênero masculino (Idade = 22,9 ± 3,9 anos) foram divididos randomicamente em dois grupos: controle, com caminhada no plano (GC, n = 8), e caminhada em declive (GCD, n = 9). Os indivíduos realizaram os seguintes procedimentos, em diferentes dias: 1) Contrações voluntárias máximas para determinar o pico de torque (PT) e a taxa de desenvolvimento de torque (TDT) em diferentes intervalos de tempo após o início da contração. Os testes foram realizados antes (Pré) e após (Pós) um período de quatro semanas de treinamento de caminhada em declive. O PT e a TDT pico não apresentaram mudança após o período de treinamento (p > 0,05). No entanto, houve aumento significante na TDT nos momentos 150 e 200 ms para o GCD (p < 0,05). Além disso, a atividade eletromiográfica (root mean square) do músculo bíceps femoral e do semitendinoso apresentou aumento após o período de treinamento (p < 0,05). Portanto, o treinamento de caminhada em declive pode promover aumento na TDT em sua fase tardia e na ativação muscular, o que pode ter implicações em condições de caminhada no declive, que podem auxiliar a estabilizar o corpo contra a perturbação gerada pelo declive.