We studied the effects of age on different physiological parameters, including those derived from the i) maximal cardiopulmonary exercise testing (CPET), ii) moderate-intensity step-transitions and iii) tensiomyography (TMG)-derived variables in moderately active women. Twenty-eight women (age range from 19 to 53 y), completed three laboratory visits, including baseline data collection, TMG assessment, VO2 max. test via CPET, and a step-transition test from 20 W to a moderate-intensity cycling power output (PO), corresponding to VO2 at 90% gas exchange threshold. During the step-transitions breath-by-breath pulmonary oxygen uptake (V%O2p), near infrared spectroscopy derived muscle deoxygenation (%HHb), and beat-by-beat cardiovascular response were continuously monitored. There were no differences observed between the young and middle-aged women in their VO2 max. and peak PO, while the HR max. was 12 bpm lower in middle-aged compared to young (p=.016). Also, no differences were observed between the age groups in VO2p, HHb, and HR during on-transients. The first regression model showed that age did not attenuate the maximal CPET capacity in the studied population (p=.638), while in the second model a faster %VO2p, We combined with shorter TMG-derived contraction time (Tc) of the vastus lateralis (VL), were associated with a higher VO2 max. (~30% of explained variance, p=.039). In conclusion, long lasting exercise involvement protects against a V˙O2 max. and VO2p deterioration in moderately active women.
COBISS.SI-ID: 26481155
This study investigated the effects of an 8-week plyometric training (PT) session on countermovement jump (CMJ) height, take-off velocity, and Tensiomyography (TMG) derived contractile parameters in seniors. Methods: Twenty-three senior adults (age 66.7±5.2 years) were randomly divided into two groups: PLYO (n=11) and CTRL (n=12). Tensiomyography was measured in vastus lateralis (VL), biceps femoris (BF), tibialis anterior (TA), gastrocnemius medialis (GM), and lateralis (GL). Additionally, the electromechanical efficiency (EME) index was calculated in GM as a ratio between amplitudes of peak-to-peak M-wave and TMG (Dm) responses. Biochemical markers of muscle damage and inflammation were evaluated to provide indirect indices of exercise protocol safety. Results: The main effect of time (for take-off velocity p=.023; ?2= .236) and group x time interactions (for CMJ, Tc (BF, GM), Dm (BF) and EME p(.05; ?2= .136 - .236) were observed. Post hoc analysis showed a significant increase in CMJ height and take-off velocity, namely by 14.2% (p=.001) and 8.2% (p=.01) in PLYO, respectively. Contraction time (Tc) decreased in BF –5.7% (p=.001) and GM –9.6% (p=.001). Dm decreased only in BF –20.8% (p=.001), while the EME index of the GM improved by 22.9% (p=.002). There were no differences between groups or assessment time points for C-reactive protein (p=.122). Conclusion: The present study clearly supports the application of supervised PT exercise in seniors, since explosive power, muscle contractility, and EME of the lower limbs were markedly improved after training.
COBISS.SI-ID: 2536915
Background: The cardiovascular response to variable load exercise on a flywheel ergometer is still unknown. Objective This study examined the effects of flywheel exercise on cardiovascular response and brachial artery vasodilation capacity in healthy active men. Methods: In this cross-sectional study, nineteen men (20 to 57 years old) completed three laboratory visits, including a ramp exercise test to determine their V˙O2 max., and an exercise intervention on a flywheel ergometer set at 0.075 kg·m2 moment of inertia. After the ramp test cessation, all participants were allocated into an aerobically untrained (n=10) and trained (n=9) groups. Throughout the flywheel exercise, cardiovascular demands were continuously monitored via Finapres, while a pre/post flow-mediated dilation (FMD) assessment was performed using ultrasound imaging. Results: There were no differences observed between the groups in their anthropometrics, age or resting brachial artery diameter, while the V˙O2 max. was ~15% higher (p=.001) in trained compared to aerobically untrained group. The cardiovascular response to the flywheel-exercise were similar between the groups, with peak mean arterial pressure and heart rate readings reaching ~160 mmHg and ~140 bpm, respectively. The flywheel exercise did not impair the FMD (%) response, which was comparable between the groups (p=.256). When these data were pooled, the regression analysis showed an inverse relationship among FMD (%), age (ß= -.936, p=.001) and V˙O2 max. (ß= -.359, p=.045). Conclusion: Although the aerobic fitness alone does not directly explain the FMD response to flywheel exercise, aerobically untrained individuals, as they get older tend to have lower brachial artery FMD.
COBISS.SI-ID: 52928771