No abstract

The authors examined the relationship between the maximum recoverable lean angle via the tether-release method with early-or late-phase rate of torque development (RTD) and maximum torque of lower-limb muscle groups in 56 young healthy adults. Maximal isometric torque and RTD at the hip, knee, and ankle were recorded. The RTD at 50-ms intervals up to 250 ms from force onset was calculated. The results of a stepwise multiple regression analysis, early RTD for hip flexion, and knee flexion were chosen as predictive variables for the maximum recoverable lean angle. The present study suggests that some of the early RTD in the lower limb muscles, but not the maximum isometric torque, can predict the maximum recoverable lean angle.

[Purpose] This study aimed to ascertain whether ankle stretching combined with arm cycling compared with that without arm cycling results in greater improvement in maximum dorsiflexion range of motion (ROM), calf muscle stiffness, and gait velocity in the affected limb of patients with stroke. [Participants and Methods] Random ABAB reversal design was used in this study involving nine patients with stroke. Participants performed 10 min of ankle plantar flexor stretching through weight bearing using the tilt table under the following 2 conditions: with or without arm cycling at 60 revolutions per minute. Pre- and post-stretching maximum ROM and passive plantar flexion torque were measured using a custom-made passive torque indicator. Stiffness was calculated based on passive torque-angle relationships. [Results] Maximum ROM and stiffness significantly improved after stretching in both conditions, whereas no changes in gait velocity were found. The difference in pre- and post-stretching stiffness was significantly greater in the stretching with arm cycling group. Change in maximum ROM showed no difference between both stretching conditions. [Conclusion] This study indicates that ankle plantar flexor stretching combined with arm cycling was more effective than that without cycling in improving calf muscle stiffness in the affected limb of patients with stroke.

Sex differences in LPD/PW and LPD/HT at a 30∘ knee flexion were detected in healthy subjects. Although the knee extension angle related to both the lateral and medial direction of the patellar mobility, the relations were only fairly correlated in asymptomatic young subjects.

This study investigated the acute effect of an 18-hole round of golf on serum interleukin-6 (IL-6) and brain-derived neurotropic factor (BDNF) concentration. Nine young, healthy males, unaccustomed to playing golf, completed an 18-hole round of golf (course length: 5,807 m.). Blood samples were collected prior to, immediately after and 1 h following completion of the exercise session. Interleukin-6 and BDNF, as well as creatine kinase (CK) and myoglobin concentrations were analysed in serum, while adrenaline concentrations were assessed in plasma. The participants completed the course in 303 ± 4 min. Serum IL-6 and BDNF concentrations were respectively elevated 8.6 ± 5.4-fold and 1.2 ± 0.3-fold immediately post-exercise (IL-6 p = 0.008; BDNF p = 0.038). Creatine kinase (p = 0.008), myoglobin (p = 0.011) and adrenaline concentrations (p = 0.038) were also acutely elevated following completion of the golf course. Creatine kinase and myoglobin concentrations were significantly correlated with the acute increase in IL-6 concentration post-exercise (r = 0.70 p = 0.034, r = 0.79 p = 0.012, respectively), while no such relationship was found for BDNF concentration. (r = 0.37 p = 0.333, r = 0.08 p = 0.833, respectively). An 18-hole round of golf was found to acutely elevate IL-6 and BDNF concentration in young, healthy males unaccustomed to playing golf. The correlation of CK and myoglobin with the acute IL-6 response suggests that muscle damage may have influenced the acute increase in this marker. Together, this pilot-study indicates that golf may be promoted as an accessible, low-intensity activity to acutely elevate markers suggested to stimulate improvements in metabolic health and cognitive function.

Tajima (2021) The effects of endurance exercise combined with high-temperature head-out water immersion on serum concentration of brain-derived neurotrophic factor in healthy young men,

Purpose] To confirm the criterion-related validity and reliability of surae muscle tendon unit stiffness measured using a custom-made passive torque indicator (CPTI), a portable device composed of an angle-adjustable foot plate and strain gauge. The data were compared to readings obtained using an isokinetic dynamometer. [Subjects and Methods] Fourteen healthy young adults participated in this study. Torques at four angles of dorsiflexion of the ankle joint of the subjects were recorded using the CPTI and a dynamometer. The slope of the portion of the passive torque-angle curve was defined as stiffness. Three measurements were performed with each device.[Results] The intra-class correlation coefficients (ICC) (1, 3) were 0.81 and 0.86 for the CPTI and dynamometer, respectively. The degree of stiffness determined using the CPTI was significantly less than that determined using the dynamometer. A Bland-Altman plot revealed there was a fixed error between the CPTI and dynamometer.[Conclusion] The results of this study indicate that three measurements with the CPTI are as reliable as those made with an isokinetic dynamometer. However, the degree of stiffness determined using the CPTI tended to be less than that determined using the dynamometer.

2) completed the exercise program and the gait evaluation. The average KAM and KFM was 0.49 Nm/kg and 0.47 Nm/kg at baseline. There was significant correlation between KAM and KFM (rho ¼-0.37, p ¼ 0.02). After the 6-week program, KAM decreased by 7.55 % to 0.45 Nm/kg (p ¼ 0.12), while KFM was significantly increased by 30.18 % to 0.62 Nm/kg (p<0.01). Though direct correlation between KAM and KFM was not significant (rho ¼-0.23, p ¼ 0.15), there existed significant correlation between decrease in KAM and increase in KFM (rho ¼-0.44, p ¼ 0.01). Conclusions: In patients with KOA, external joint loading along the sagittal and frontal plane was related. A higher peak knee adduction moment was associated with a lower knee flexion moment. More importantly, a greater reduction of knee adduction moment was associated with a greater increase in the knee flexion moment after a 6week exercise program. Such information might suggest exerciseinduced transforming of joint loading along the sagittal and frontal plane. Also, the efficacy of exercise program might associate with its direct effects on increasing the knee flexion moments than reducing the knee adduction moments in patients with KOA.