Muscle-Skeletal Abnormalities and Muscle Oxygenation during Isokinetic Strength Exercise in Heart Failure with Preserved Ejection Fraction Phenotype: A Cross-Sectional Study

Exercise intolerance, a hallmark of patients with heart failure (HF), is associated with muscle weakness. However, its causative microcirculatory and muscle characteristics among those with preserved or reduced ejection fraction (HFpEF or HFrEF) phenotype is unclear. The musculoskeletal abnormalities that could result in impaired peripheral microcirculation are sarcopenia and muscle strength reduction in HF, implying lowered oxidative capacity and perfusion affect transport and oxygen utilization during exercise, an essential task from the microvascular muscle function. Besides that, skeletal muscle microcirculatory abnormalities have also been associated with exercise intolerance in HF patients who also present skeletal muscle myopathy. This cross-sectional study aimed to compare the muscle microcirculation dynamics via near-infrared spectroscopy (NIRS) response during an isokinetic muscle strength test and ultrasound-derived parameters (echo intensity was rectus femoris muscle, while the muscle thickness parameter was measured on rectus femoris and quadriceps femoris) in heart failure patients with HFpEF and HFrEF phenotypes and different functional severities (Weber Class A, B, and C). Twenty-eight aged-matched patients with HFpEF (n = 16) and HFrEF (n = 12) were assessed. We found phenotype differences among those with Weber C severity, with HFrEF patients reaching lower oxyhemoglobin (O2Hb, μM) (−10.9 ± 3.8 vs. −23.7 ± 5.7, p = 0.029) during exercise, while HFpEF reached lower O2Hb during the recovery period (−3.0 ± 3.4 vs. 5.9 ± 2.8, p = 0.007). HFpEF with Weber Class C also presented a higher echo intensity than HFrEF patients (29.7 ± 8.4 vs. 15.1 ± 6.8, p = 0.017) among the ultrasound-derived variables. Our preliminary study revealed more pronounced impairments in local microcirculatory dynamics in HFpEF vs. HFrEF patients during a muscle strength exercise, combined with muscle-skeletal abnormalities detected via ultrasound imaging, which may help explain the commonly observed exercise intolerance in HFpEF patients.

A remote Tai Chi program for diverse older adults with multisite pain during the COVID-19 pandemic

The goal of this study was to evaluate feasibility and acceptability of a remote Tai Chi program in diverse older adults with multisite pain and risk for falls during the COVID-19 pandemic. Adults aged ≥65y living in diverse Boston neighborhoods were invited through mailed letters to participate in a recruitment and screening survey. Eligible adults were re-contacted to join a 4-week Tai Chi or light exercise program offered online twice weekly. We conducted pre- and post-interviews to assess pain characteristics, fall risk, computer use, and satisfaction with the program. Primary outcomes were class attendance, experience, and program safety. Among 335 survey respondents, 105 (31%) were eligible based on multisite pain and fall history or cane/walker use. Of the eligible respondents, average age was 74y, 75% were women, 62% were Black, and 31% had high school education or less. We assigned 32 participants to 4 Tai Chi (Yang-style Tai Chi tailored to older adults with pain) or 2 light exercise (stretching and strength exercise) groups conducted via zoom; of these, 24 (75%) completed the program. Overall, 79% attended ≥6 of 8 classes. There were no adverse events reported. Regarding experiences with remote exercise, 67% reported it was very easy to join, 88%, very easy to see the instructor and 83%, very easy to participate. For future planning, 29% prefer remote classes, 33% prefer in-person classes, and 38% could do either. In conclusion, remote exercise programming is safe and feasible for diverse older adults who have multisite pain and risk of falls.

Effects of Training Status and Exercise Mode on Global Gene Expression in Skeletal Muscle

The aim of this study was to investigate differences in skeletal muscle gene expression of highly trained endurance and strength athletes in comparison to untrained individuals at rest and in response to either an acute bout of endurance or strength exercise. Endurance (ET, n = 8, ⩒O2max 67 ± 9 mL/kg/min) and strength athletes (ST, n = 8, 5.8 ± 3.0 training years) as well as untrained controls (E-UT and S-UT, each n = 8) performed an acute endurance or strength exercise test. One day before testing (Pre), 30 min (30′Post) and 3 h (180′Post) afterwards, a skeletal muscle biopsy was obtained from the m. vastus lateralis. Skeletal muscle mRNA was isolated and analyzed by Affymetrix-microarray technology. Pathway analyses were performed to evaluate the effects of training status (trained vs. untrained) and exercise mode-specific (ET vs. ST) transcriptional responses. Differences in global skeletal muscle gene expression between trained and untrained were smaller compared to differences in exercise mode. Maximum differences between ET and ST were found between Pre and 180′Post. Pathway analyses showed increased expression of exercise-related genes, such as nuclear transcription factors (NR4A family), metabolism and vascularization (PGC1-α and VEGF-A), and muscle growth/structure (myostatin, IRS1/2 and HIF1-α. The most upregulated genes in response to acute endurance or strength exercise were the NR4A genes (NR4A1, NR4A2, NR4A3). The mode of acute exercise had a significant effect on transcriptional regulation Pre vs. 180′Post. In contrast, the effect of training status on human skeletal muscle gene expression profiles was negligible compared to strength or endurance specialization. The highest variability in gene expression, especially for the NR4A-family, was observed in trained individuals at 180′Post. Assessment of these receptors might be suitable to obtain a deeper understanding of skeletal muscle adaptive processes to develop optimized training strategies.

Strength exercise for balance and gait in HIV-associated distal symmetrical polyneuropathy: A randomised controlled trial

Background: HIV-associated peripheral neuropathy (PN) is a common neurological complication associated with HIV infection. Distal symmetrical polyneuropathy (DSPN) is the most commonly occurring type, which is associated with symptoms such as numbness, unsteady gait and, in some cases, muscle atrophy and weakness when myelinated nerve fibres are affected. If unmyelinated nerve fibres are affected, a painful neuropathy and autonomic symptoms may occur.Objectives: This research study assessed the effects of a strength exercise intervention on balance impairment and gait disturbance amongst individuals living with HIV-associated DSPN.Method: The study was a single-blinded, randomised controlled trial (RCT) with participants sourced from four HIV centres in Kano metropolis, Nigeria. The intervention was supervised and included progressive resistance exercise (PRE) (three 40-min sessions per week for 12 weeks) using a quadriceps bench (n = 44). The control group (CG) included the non-exercise group (n = 47). The two groups continued to receive routine care. Data were summarised and analysed using inferential statistics (SPSS version 20 program) with the alpha level set at 0.05.Results: At 12 weeks, the results revealed significant improvement with regard to balance performance (p = 0.001) and walking ability (p = 0.001) in the training group. In contrast, no significant differences in balance (P = 0.677) or gait (P = 0.578) were observed in the CG.Conclusion: The findings suggest that PRE is beneficial for balance impairment and gait disturbance caused by neuropathy in persons living with HIV and receiving antiretroviral drugs.

Acute Effects of Moderate versus High-Intensity Strength Exercise on Attention and Mood States in Female Physical Education Students

The presumed benefits of exercise/physical activity on the brain are an important public health issue. However, the experimental approach to understanding the effects of physical activity on the brain, and more particularly on cognitive functions, has only been studied recently. In particular, females remain underrepresented in the research, despite having a specific training/exercise adaptation/response. The aim of the present study was to examine the acute effects of high- and moderate-intensity strength exercise (3 sets of 8–10 repetitions and 3 sets of 6 repetitions, respectively, with each session lasting approximately 30 min) on attention and mood states in female physical education students. Forty-six female physical education students (Mage = 20.02 ± 1.05 years, MBody Mass Index = 21.07) volunteered to participate in this study. They were divided into three groups: a moderate-intensity strength exercise group (MISEG: n = 15), a high-intensity strength exercise group (HISEG: n = 16), and a control group (CG: n = 15). Attention and psychological states were assessed using the d2 test, Rating of Perceived Exertion (RPE) and the Brunel Mood Scale (BRUMS) questionnaire, respectively, before and after each session. The data showed that in the MISEG attention increased, in terms of concentration (p = 0.05). RPE values, fatigue and confusion were higher for the HISEG than the CG (p < 0.05) and the MISEG (p < 0.05). Vigour was higher for the MISEG than other groups (p < 0.05). In conclusion, moderate-intensity resistance exercise is an appropriate method to improve attention in female participants. The elevated cognitive performance may be due to the changes in RPE and mood states (fatigue, vigour and confusion subscales).

Acute Impacts of Different Types of Exercise on Circulating α-Klotho Protein Levels

Introduction: Elevated plasma α-klotho (αKl) protects against several ageing phenotypes and has been proposed as a biomarker of a good prognosis for different diseases. The beneficial health effects of elevated plasma levels of soluble αKl (SαKl) have been likened to the positive effects of exercise on ageing and chronic disease progression. It has also been established that molecular responses and adaptations differ according to exercise dose. The aim of this study is to compare the acute SαKl response to different exercise interventions, cardiorespiratory, and strength exercise in healthy, physically active men and to examine the behavior of SαKl 72h after acute strength exercise.Methods: In this quasi-experimental study, plasma SαKl was measured before and after a cardiorespiratory exercise session (CR) in 43 men, and strength exercise session (ST) in 39 men. The behavior of SαKl was also examined 24, 48, and 72h after ST.Results: Significant differences (time×group) were detected in SαKl levels (p=0.001; d=0.86) between CR and ST. After the ST intervention, SαKl behavior varied significantly (p=0.009; d=0.663) in that levels dropped between pre- and post-exercises (p=0.025; d=0.756) and were also significantly higher compared to pre ST values at 24h (p=0.033; d=0.717) and at 48h (p=0.015; d=0.827).Conclusions: SαKl levels increased in response to a single bout of cardiorespiratory exercise; while they decreased immediately after strength exercise, levels were elevated after 24h indicating different klotho protein responses to different forms of exercise.

Validation of a Smartwatch-Based Workout Analysis Application in Exercise Recognition, Repetition Count and Prediction of 1RM in the Strength Training-Specific Setting

The goal of this study was to assess the validity, reliability and accuracy of a smartwatch-based workout analysis application in exercise recognition, repetition count and One Repetition Maximum (1RM) prediction in the strength training-specific setting. Thirty recreationally trained athletes performed four consecutive sets of barbell deadlift, barbell bench press and barbell back squat exercises with increasing loads from 60% to 80% of their estimated 1RM with maximum lift velocity. Data was measured using an Apple Watch Sport and instantaneously analyzed using an iOS workout analysis application called StrengthControl. The accuracies in exercise recognition and repetition count, as well as the reliability in predicting 1RM, were statistically analyzed and compared. The correct strength exercise was recognised in 88.4% of all the performed sets (N = 363) with accurate repetition count for the barbell back squat (p = 0.68) and the barbell deadlift (p = 0.09); however, repetition count for the barbell bench press was poor (p = 0.01). Only 8.9% of attempts to predict 1RM using the StrengthControl app were successful, with failed attempts being due to technical difficulties and time lag in data transfer. Using data from a linear position transducer instead, significantly different 1RM estimates were obtained when analysing repetition to failure versus load-velocity relationships. The present results provide new perspectives on the applicability of smartwatch-based strength training monitoring to improve athlete performance.