Load carriage aerobic exercise stimulates a transient rise in biochemical markers of bone formation and resorption

Load carriage exercise increases calcium absorption and retention in healthy young women

Aerobic exercise reduces circulating ionized Ca (iCa) and increases parathyroid hormone (PTH), but the cause and consequences on Ca handling are unknown. The objective of this study was to determine the effects of strenuous exercise on Ca kinetics using dual stable Ca isotopes. Twenty-one healthy women (26.4 ± 6.7 yr) completed a randomized, crossover study entailing two 6-d iterations consisting of either 60 min of treadmill walking at 65% VO2max wearing a vest weighing 30% body weight on study days 1, 3, and 5 (exercise [EX]), or a rest iteration (rest [REST]). On day 1, participants received intravenous 42Ca and oral 44Ca. Isotope ratios were determined by thermal ionization mass spectrometry. Kinetic modeling determined fractional Ca absorption (FCA), Ca deposition (Vo+), resorption (Vo-) from bone, and balance (Vbal). Circulating PTH and iCa were measured before, during, and after each exercise/rest session. Data were analyzed by paired t-test or linear mixed models using SPSS. iCa decreased and PTH increased (P < .001) during each EX session and were unchanged during REST. On day 1, urinary Ca was lower in the EX pool (25 ± 11 mg) compared to REST (38 ± 16 mg, P = .001), but did not differ over the full 24-h collection (P > .05). FCA was greater during EX (26.6 ± 8.1%) compared to REST (23.9 ± 8.3%, P < .05). Vbal was less negative during EX (-61.3 ± 111 mg) vs REST (-108 ± 23.5 mg, P < .05), but VO+ (574 ± 241 vs 583 ± 260 mg) and VO- (-636 ± 243 vs -692 ± 252 mg) were not different (P > .05). The rapid reduction in circulating iCa may be due to a change in the miscible Ca pool, resulting in increased PTH and changes in intestinal absorption and renal Ca handling that support a more positive Ca balance.

Effect of acute resistance exercise on bone turnover in young adults before and after concurrent resistance and interval training

Weight-bearing physical activity can stimulate bone adaptation. This investigation explored the effect of an acute bout of resistance exercise before and after resistance+interval training on circulating biomarkers of bone metabolism and muscle-bone crosstalk. Healthy young male and female participants (n = 21 male, 28 ± 4 years; n = 17 female, 27 ± 5 years) performed a 6 × 10 squat test (75% 1RM) before and after a 12-week resistance+interval training program. Before and after completion of the training program, blood samples were collected at rest, immediately postexercise, and 2 h postexercise. Blood samples were analyzed for βCTX, P1NP, sclerostin, osteocalcin, IGF-1, and irisin. Significant effects of acute exercise (main effect of time) were observed as increases in concentrations of IGF-1, irisin, osteocalcin, and P1NP from rest to postexercise. A sex*time interaction indicated a greater decline in βCTX concentration from rest to 2 h postexercise and a greater increase in sclerostin concentration from rest to immediately postexercise in male compared with female participants. Sex differences (main effect of sex) were also observed for irisin and P1NP concentrations. In summary, changes in concentrations of biochemical markers of bone metabolism and muscle-bone crosstalk were observed in males and females after an acute bout of resistance exercise and following 12 weeks of resistance+interval training.

The role and regulation mechanism of Chinese traditional fitness exercises on the bone and cartilage tissue in patients with osteoporosis: A narrative review

Osteoporosis (ops) is a systemic degenerative bone disease characterized by bone mass reduction, bone mineral density loss, bone microstructure destruction, bone fragility, and increased fracture susceptibility. Thus far, drug therapy is the main method used to prevent and treat osteoporosis. However, long-term drug treatment will inevitably lead to drug resistance and certain side effects. In response, rehabilitation treatment is generally recommended, which involves drug supplementation combined with the treatment. A Chinese traditional fitness exercise is an organic combination of sports and traditional Chinese medicine with a series of advantages such as being safe, convenient, non-toxic, and harmless. Hence, it is one of the rehabilitation methods widely used in clinical practice. By searching the CNKI, PubMed, Web of Science, Embase, Cochrane Library, and other relevant databases, our research clarifies the current situation of four kinds of Chinese traditional fitness exercises widely used in clinical practice, namely, Taijiquan, Baduanjin, Wuqinxi, and Yijin Jing. In addition, the molecular mechanism of osteoporosis is summarized in this study. Based on the research, Chinese traditional fitness exercises are expected to directly stimulate the bone through a mechanical load to improve bone density. Moderate and regular traditional Chinese fitness exercises also improve osteoporosis by regulating the endocrine system with the secretion of hormones and factors such as estrogen and irisin, which are beneficial for bone formation. Finally, the purpose of promoting bone formation, reducing bone loss, and preventing and treating osteoporosis is achieved. The various means of Chinese traditional fitness exercises have different emphases, and the effect of improving bone density differs in various parts of the body. The exercisers may choose the exercise flexibly based on their own needs. Chinese traditional fitness exercises can improve the bone density of the exercisers and relieve pain, improve balance, and regulate the psychological state. Consequently, it is worth promoting to be applied in clinical practices.