Background and objectives: Telomere length is an indicator of biological aging, and it shortens during cell division. A short telomere length is associated with various age-related diseases and mortality. It is suggested that physical activity has a positive effect on the rate of telomere length shortening. Materials and Methods: Related studies, published in electronic databases, were searched with keywords, including exercise, telomere length, and randomized controlled trial. The data were weighted and pooled through a fixed-effect model. Results: Of the total 49 studies searched, 7 studies with 939 participants were considered suitable, and were analyzed qualitatively and quantitatively. Exercise is beneficial to telomere length. Aerobic exercise was effective as the type of exercise (MD, −0.03; 95% CI, −0.04 to −0.01). In addition, exercise for more than 6 months, with a change in lifestyle, is beneficial for telomere length (MD, −0.02; 95% CI, −0.04 to −0.01). Conclusions: The type and duration of exercise for positive improvement in telomere length is aerobic exercise for more than 6 months.

Hyunjoong Kim, Seungwon Lee. PTRS 2020;9:309-17. https://doi.org/10.14474/ptrs.2020.9.4.309

This systematic review aimed to synthesize and quantify the results of the studies investigating the changes in fibroblast growth factor-21 (FGF-21) induced by exercise. We searched for studies that did not differentiate between patients and healthy adults but compared them before and after exercise and with and without exercise. For quality assessment, the risk-of-bias assessment tool for nonrandomized studies and the Cochrane risk-of-bias tool were used. A quantitative analysis was performed using the standardized mean difference (SMD) and random-effects model in RevMan 5.4. A total of 94 studies were searched in international electronic databases, and after screening, 10 studies with 376 participants were analyzed. Compared with no exercise, there was a significant increase in the FGF-21 levels from before to after exercise (SMD = 1.05, 95% confidence interval (CI), 0.21 to 1.89). The changes in FGF-21 levels in the exercise group showed a significant difference from the levels in the controls. The results of the random-effects model were as follows: SMD = 1.12; 95% CI, −0.13 to 2.37. While the data on acute exercise were not synthesized in this study, FGF-21 levels generally increased after chronic exercise compared with no exercise.

Patellofemoral pain syndrome (PFPS) is defined as pain around the patella while performing activities such as squats, running, and climbing steps. One of the inherent risk factors for PFPS is an excessively pronated foot posture. The aim of this study was to investigate the effect of foot intervention, talonavicular joint mobilization (TJM) and foot core strengthening (FCS), on PFPS. Forty-eight patients with PFPS (mean age, 21.96 ± 2.34 years; BMI, 22.77 ± 2.95 kg/m²) were enrolled in the study. Participants were randomly assigned in a 1:1:1 ratio to three groups, and received 12 sessions of TJM, FCS, and blended intervention at university laboratory for 4 weeks. The primary outcomes were pain while the secondary outcomes were lower extremity function, valgus knee, foot posture, and muscle activity ratio measured at baseline, after 12 sessions, and at the 4-week follow-up. The two-way repeated-measures ANOVA revealed significant interactions in all groups (p < 0.05). TJM reduced pain more than the FCS at post-test (mean difference, − 0.938; 95% Confidence interval [CI], − 1.664 to − 0.211; p < 0.05), and blended intervention improved lower extremity function (mean difference, 6.250; 95% CI, 1.265 to 11.235; p < 0.05) and valgus knee (mean difference, − 11.019; 95% CI, − 17.007 to − 5.031; p < 0.05) more than the TJM at 4 weeks follow-up. TJM was more effective in post-test (mean difference, − 1.250; 95% CI, − 2.195 to − 0.305; p < 0.05), and TJM (mean difference, − 1.563; 95% CI, − 2.640 to − 0.485; p < 0.05) and blended intervention (mean difference, − 1.500; 95% CI, − 2.578 to − 0.422; p < 0.05) were more effective in foot posture than the FCS in 4 weeks follow-up. Blended intervention displayed greater improvement in muscle activity than the TJM (mean difference, 0.284; 95% CI, 0.069 to 0.500; p < 0.05) and the FCS (mean difference, 0.265; 95% CI, 0.050 to 0.481; p < 0.05) at 4 weeks follow-up. Our study is a novel approach to the potential impact of foot interventions on patellofemoral pain. Foot intervention including TJM and FCS is effective for pain control and function improvement in individuals with PFPS. KCT0003176, 16/08/2018 (retrospectively registered).

This study was conducted to demonstrate the therapeutic effect of soft-tissue mobilization (STM) combined with pain neuroscience education (PNE) for patients with chronic nonspecific low back pain with central sensitization. A total of 28 participants were recruited and randomly allocated to either the STM group (SMG) (n = 14) or the STM plus PNE group (BG; blended group) (n = 14). STM was applied twice a week for four weeks, with a total of eight sessions, and PNE was applied within four weeks, for a total of two sessions. The primary outcome was pain intensity, and the secondary outcomes were central sensitization, pressure pain, pain cognition, and disability. Measurements were made at baseline, after the test, and at 2-week and 4-week follow-ups. The BG showed significant improvement in pain intensity (p < 0.001), pressure pain (p < 0.001), disability (p < 0.001), and pain cognition (p < 0.001) compared to the SMG. This study demonstrated that STM plus PNE is more effective for all measured outcomes compared to STM alone. This finding suggests that the combination of PNE and manual therapy has a positive effect on pain, disability index, and psychological factors in the short term.

Sensorimotor and range of motion deficits due to chronic ankle instability (CAI) are abnormalities of the movement system that make postural control difficult. This review aimed to quantify the effect of joint mobilization on the range of motion, dynamic balance, and function in individuals with CAI. Randomized controlled trials in which joint mobilization was performed in individuals with CAI were searched for in five international databases (CENTRAL, CINAHL, Embase, MEDLINE, PEDro). Qualitative and quantitative analyses were performed using the risk of bias tool and RevMan 5.4 provided by the Cochrane Library. Nine studies with 364 individuals with CAI were included in this study. This meta-analysis reported that joint mobilization showed significant improvement in the dorsiflexion range of motion (standardized mean difference [SMD] = 1.02, 95% confidence interval [CI]: 0.41 to 1.63) and dynamic balance (SMD = 0.49, 95% CI: 0.06 to 0.78) in individuals with CAI. However, there was no significant improvement in function (patient-oriented outcomes) (SMD = 0.76, 95% CI: −0.00 to 1.52). For individuals with CAI, joint mobilization has limited function but has positive benefits for the dorsiflexion range of motion and dynamic balance.