Metabolic Consequences of Anabolic Steroids, Insulin, and Growth Hormone Abuse in Recreational Bodybuilders: Implications for the World Anti-Doping Agency Passport.

BACKGROUND: Hormonal doping in recreational sports is a public-health concern. The World Anti-Doping Agency (WADA) promoted the creation of the Athlete Biological Passport, aiming to monitor athlete's biological variables over time to facilitate indirect detection of doping. Detection tests for anabolic androgenic steroids (AAS) and growth hormone (GH) are available while insulin abuse cannot be revealed. We have determined in recreational bodybuilders the metabolic effects associated with different patterns of hormone abuse. All analyses were conducted using Statistical Package for Social Sciences (SPSS) 21.0 software (SPSS Chicago, IL). RESULTS: We have assessed plasma concentrations of selected metabolic markers and fatty acid content in erythrocyte membranes of 92 male bodybuilders and in 45 healthy controls. Hormonal abuse was identified by anonymous questionnaires. 43% (%) of recruited bodybuilders regularly abused hormones, i.e., anabolic androgenic steroids (95%) often associated with GH (30%) and/or insulin (38%). HDL-cholesterol was lower in insulin and/or GH abusers. Alanine (ALT) and aspartic (AST) transaminases were greater in hormone abusing bodybuilders than in non-doping bodybuilders and controls. Insulin doping was selectively associated with increased plasma ALT-to-AST ratio. In erythrocyte membranes, elongase activity (i.e., stearic-to-palmitic ratio) was lower in insulin and/or growth hormone doping, whereas increased Δ-9 desaturase activity (i.e., palmitoleic-to-palmitic ratio) was selectively associated with insulin doping. CONCLUSIONS: In conclusion, our study demonstrates that insulin and GH abuse are characterized by multiple alterations of specific metabolic markers. Although further studies are needed to test whether longitudinal monitoring of selected metabolic marker such as muscle contraction time, HDL levels, ALT-AST ratio as well as the activities of selected enzymes (e.g. Δ-9 desaturase and elongase), could contribute to the detection of insulin and GH abuse in sport.

Retinal venular vessel diameters are smaller during ten days of bed rest.

Older individuals experience cardiovascular dysfunction during extended bedridden hospital or care home stays. Bed rest is also used as a model to simulate accelerated vascular deconditioning occurring during spaceflight. This study investigates changes in retinal microcirculation during a ten-day bed rest protocol. Ten healthy young males (22.9 ± 4.7 years; body mass index: 23.6 ± 2.5 kg·m-2) participated in a strictly controlled repeated-measures bed rest study lasting ten days. High-resolution images were obtained using a hand-held fundus camera at baseline, daily during the 10 days of bed rest, and 1 day after re-ambulation. Retinal vessel analysis was performed using a semi-automated software system to obtain metrics for retinal arteriolar and venular diameters, central retinal artery equivalent and central retinal vein equivalent, respectively. Data analysis employed a mixed linear model. At the end of the bed rest period, a significant decrease in retinal venular diameter was observed, indicated by a significantly lower central retinal vein equivalent (from 226.1 µm, CI 8.90, to 211.4 µm, CI 8.28, p = .026), while no significant changes in central retinal artery equivalent were noted. Prolonged bed rest confinement resulted in a significant (up to 6.5%) reduction in retinal venular diameter. These findings suggest that the changes in retinal venular diameter during bedrest may be attributed to plasma volume losses and reflect overall (cardio)-vascular deconditioning.

Participation in youth sports influences sarcopenia parameters in older adults.

Background: The degree of deterioration in sarcopenia parameters may be affected by a person's level of physical activity (PA) and sedentary behavior (SB). Our study focused on examining the PA and SB of active older adults including those with and without history of sports in youth. Methods: Forty-four participants (20 men and 24 women, mean age of total sample 76.1 ± 5.2 years) were included in analysis of PA, SB habits and sarcopenia parameters, determined by skeletal muscle index, hand-grip strength, gait speed, Timed Up and Go tests (TUG). PA and SB were recorded with accelerometers. Our primary aim was to compare participants with (AH) or without a sport history in youth (NAH), in their sarcopenia parameters and PA and SB habits. Results: When divided participants in two groups (AH and NAH) and adjusting for age, we have detected the differences for skeletal muscle index (p = 0.007) and hand-grip strength (p = 0.004) in favor of participants who were engaged in sports in youth. We did not find any differences in PA and SB habits between the AH and NAH groups. After adjusting for age, participants with a higher number of daily steps, longer moderate to vigorous physical activity (MVPA) bouts, a higher number of MVPA bouts in a day and higher overall MVPA engagement achieved better results in hand-grip strength and TUG. Participants with lower SB had better TUG and gait speed results. Conclusions: Our findings suggest that engaging in sports activities in youth can make a difference with sarcopenia parameters. Although we found no differences in PA and SB habits between participants with AH and NAH, participants with an athlete history performed better results in sarcopenia parameters.

Functional characteristics and subjective disease perception in patients with COVID-19 two months after hospital discharge.

Introduction: Although early inpatient and post-hospital rehabilitation is recognized as necessary, not all COVID-19 patients have access to rehabilitation. There are no published reports in the literature that investigate the outcomes of patients who do not receive rehabilitation after COVID-19. Our aim was to evaluate possible improvements in determinate functional and psychological parameters in COVID-19 patients two months after their hospital discharge. Methods: On both time points various motor, cognitive, and clinical measurements such as body composition, tensiomyography, blood pressure, spirometry, grip strength test, Timed Up and Go test, gait speed, 30-second chair-stand test, and Montreal Cognitive Assessment, were performed. Additionally, questionnaires such as the SARC-CalF test, Edmonton frail scale, International Physical Activity questionnaire andThe Mediterranean Lifestyle index were conducted to assess lifestyle characteristics. Results: A total of 39 patients (87.2% male; mean age of 59.1 ± 10.3 years), who were hospitalized due to COVID-19 at the Izola General Hospital (IGH), Slovenia between December 2020 and April 2021, were included. Patients were assessed at two time points (T1 and T2): T1 was taken after receiving a negative COVID-19 test and T2 was taken two months after T1. After two months of self-rehabilitation, we have detected a BMI increase (p < .001), fat free mass increase (p < .001), better Edmonton frail scale (p < .001), SARC-CalF score (p = .014) and MoCA score (p = .014). There were no detected changes in lifestyle habits nor in physical performance tests. Discussion: It is already known that COVID-19 has long-term negative consequences regardless of the stage of the disease. Our findings support the notion that patients cannot fully regain all their functions within a two-month period without receiving structured or supervised rehabilitation. Therefore, it is crucial to offer patients comprehensive and structured rehabilitation that incorporates clinical, cognitive, and motor exercises.

Trunk muscles' characteristics in adolescent gymnasts with low back pain: a pilot study on the effects of a physiotherapy intervention including a postural reeducation program.

BACKGROUND: Trunk muscles' function and characteristics are of great importance for both static and dynamic tasks in different sports, and abnormalities of trunk flexors and extensors might be associated with low back pain (LBP). The aim of this study was to provide a comprehensive evaluation of the functional, morphological and contractile properties in trunk flexors and extensors of young gymnasts with and without LBP. METHODS: Young gymnasts (14/25 females, 14-18 y) were screened for the presence of chronic LBP. Abdominal and lumbar muscles were tested for function (McGill's endurance tests), thickness (ultrasound), and contractile responses (tensiomyography). An 8-sessions physiotherapy intervention including postural reeducation was performed by a subsample of 10 subjects with LBP. RESULTS: LBP was found to be associated to higher flexors-to-extensors endurance ratio (OR 11.250, 95% CI: 1.647-76.849, p = 0.014), reduced mean lumbar multifidus thickness (OR 16.500, 95% CI: 2.246-121.228, p = 0.006), and reduced mean erector spinae radial displacement (OR 16.500, 95% CI: 2.246-121.228, p = 0.006). The physiotherapy intervention was found to reduce LBP symptoms and it was associated with a significant improvement in the flexors-to-extensors ratio (p < 0.001). CONCLUSIONS: This study provides preliminary evidence of functional, morphological, and contractile trunk muscles' alterations associated with chronic LBP in young gymnasts, and presents the effects of a postural reeducation program on symptoms and muscles' functional properties.

The use of tensiomyography in older adults: a systematic review.

Introduction: Aging of skeletal muscles results in a cascade of events negatively affecting muscle mass, strength, and function, leading to reduced mobility, increased risk of falls, disability, and loss of independence. To date, different methods are used to assess muscle mechanical function, tensiomyography (TMG) being one of them. The aim of this review was twofold: to summarize the evidence-based usefulness of tensiomyography in older adults and to establish reference values for the main tensiomyography parameters in older adults. Methods: The PubMed, Web of Science, SPORTDiscus, and tensiomyography databases were searched from inception until 25 December 2022. Studies investigating older adults (aged 60+ years) that reported tensiomyography-derived parameters such as contraction time (Tc) and/or maximal displacement (Dm) were included. Methodological quality was assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Results: In total, eight studies satisfied the inclusion criteria. Tensiomyography has been used on different groups of older adults, including asymptomatic, master athletes, patients with peripheral arterial disease, and patients with end-stage knee osteoarthritis with a mean age of 71.5 ± 5.38 (55.7% male subjects). The most evaluated were leg muscles such as vastus lateralis (VL), gastrocnemius medialis (GM), and biceps femoris (BF). The present review demonstrates that tensiomyography is used to assess neuromuscular function in asymptomatic and diseased older adults. When compared to asymptomatic individuals, power master athletes, knee osteoarthritis patients, and patients diagnosed with peripheral arterial disease have the shortest Tc in BF, VL, and GM muscles, respectively. On the other hand, endurance master athletes showed the longest Tc in all three evaluated muscles. Less mobile, nursing-home residents showed higher Dm in VL and BF, while lower Dm in GM than the asymptomatic group. The knee osteoarthritis group showed the largest Dm in BF and VL while having the smallest Dm in GM. Conclusion: Tensiomyography can serve as a valuable tool for assessing neuromuscular function in older adults. The method is sensitive to muscle composition, architecture, and (pre) atrophic changes of the skeletal muscles and might be responsive to muscle quality changes in aging and diseased populations. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=402345, identifier CRD42023402345.

A pilot study: Exploring the influence of COVID-19 on cardiovascular physiology and retinal microcirculation.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) affects the cardiovascular system. The current study investigated changes in heart rate (HR), blood pressure (BP), pulse wave velocity (PWV), and microcirculation in patients recovering from Coronavirus disease 2019 (COVID-19) infection. METHODOLOGY: Out of 43 initially contacted COVID-19 patients, 35 (30 males, 5 females; age: 60 ± 10 years; and body mass index (BMI): 31.8 ± 4.9) participated in this study. Participants were seen on two occasions after hospital discharge; the baseline measurements were collected, either on the day of hospital discharge if a negative PCR test was obtained, or on the 10th day after hospitalization if the PCR test was positive. The second measurements were done 60 days after hospitalization. The vascular measurements were performed using the VICORDER® device and a retinal blood vessel image analysis. RESULTS: A significant increase in systolic BP (SBP) (from 142 mmHg, SD: 15, to 150 mmHg, SD: 19, p = 0.041), reduction in HR (from 76 bpm, SD: 15, to 69 bpm, SD: 11, p = 0.001), and narrower central retinal vein equivalent (CRVE) (from 240.94 µm, SD: 16.05, to 198.05 µm, SD: 17.36, p = 0.013) were found. Furthermore, the trends of increasing PWV (from 11 m/s, SD: 3, to 12 m/s, SD: 3, p = 0.095) and decreasing CRAE (from 138.87 µm, SD: 12.19, to 136.77 µm, SD: 13.19, p = 0.068) were recorded. CONCLUSION: The present study investigated cardiovascular changes following COVID-19 infection at two-time points after hospital discharge (baseline measurements and 60 days post-hospitalization). Significant changes were found in systolic blood pressure, heart rate, and microvasculature indicating that vascular adaptations may be ongoing even weeks after hospitalization from COVID-19 infection. Future studies could involve conducting additional interim assessments during the active infection and post-infection periods.

Effects of COVID-19 on cognition and mood after hospitalization and at 2-month follow-up.

A plethora of evidence links SARS-CoV-2 infection with concomitant cognitive dysfunction, which often persists weeks to months after the acute stages of illness and affects executive function, attention, memory, orientation, and movement control. It remains largely unclear which conditions or factors exacerbate the recovery. In a cohort of N=37 Slovenian patients (5 females, aged M = 58, SD = 10.7 years) that were hospitalized because of COVID-19, the cognitive function and mood states were assessed immediately after discharge and 2-months later to investigate the early post-COVID recovery changes. We assessed the global Montreal Cognitive Assessment (MoCA), Simple and Choice Reaction Times, executive functions (Trail-Making Test - TMT-A and TMT-B), short-term memory (Auditory Verbal Learning Test - AVLT), and visuospatial memory. We monitored depressive and anxiety symptoms and applied general self-efficacy and cognitive complaints questionnaires. Our results showed a global cognitive impairment (MoCA, Z = 332.5; p = 0.012), poorer performance on executive functions (TMT-A, Z = 188; p = 0.014; and TMT-B, Z = 185; p = 0.012), verbal memory (AVLT, F = 33.4; p < 0.001), and delayed recall (AVLT7, F = 17.1; p < 0.001), and higher depressive (Z = 145; p = 0.015) and anxiety (Z = 141; p = 0.003) symptoms after hospital discharge compared to 2-month follow-up, indicating that SARS-CoV-2 may transiently impair cognitive function and adversely affect the mood. No improvement in MoCA was observed in 40.5% of the patients at follow-up, indicating possible long-term effects of COVID-19 on global cognitive performance. Medical comorbidities (p = 0.035) significantly predicted the change in MoCA score over time, while fat mass (FM, p = 0.518), Mediterranean diet index (p = .0.944), and Florida Cognitive Activities Score (p = 0.927) did not. These results suggest that the patients' medical comorbidities at the time of SARS-CoV-2 infection could importantly contribute to the acute impairment of cognitive function and stress the importance of systemic implementation of countermeasures to limit the negative consequences on public health.

Pathophysiological mechanisms of reduced physical activity: Insights from the human step reduction model and animal analogues.

Physical inactivity represents a heavy burden for modern societies and is spreading worldwide, it is a recognised pandemic and is the fourth cause of global mortality. Not surprisingly, there is an increasing interest in longitudinal studies on the impact of reduced physical activity on different physiological systems. This narrative review focuses on the pathophysiological mechanisms of step reduction (SR), an experimental paradigm that involves a sudden decrease in participants' habitual daily steps to a lower level, mimicking the effects of a sedentary lifestyle. Analogous animal models of reduced physical activity, namely, the "wheel-lock" and the "cage reduction" models, which can provide the foundation for human studies, are also discussed. The empirical evidence obtained thus far shows that even brief periods of reduced physical activity can lead to substantial alterations in skeletal muscle health and metabolic function. In particular, decrements in lean/muscle mass, muscle function, muscle protein synthesis, cardiorespiratory fitness, endothelial function and insulin sensitivity, together with an increased fat mass and inflammation, have been observed. Exercise interventions seem particularly effective for counteracting these pathophysiological alterations induced by periods of reduced physical activity. A direct comparison of SR with other human models of unloading, such as bed rest and lower limb suspension/immobilisation, is presented. In addition, we propose a conceptual framework aiming to unravel the mechanisms of muscle atrophy and insulin resistance in the specific context of reduced ambulatory activity. Finally, methodological considerations, knowledge gaps and future directions for both animal and human models are also discussed in the review.

Effectiveness of 448-kHz Capacitive Resistive Monopolar Radiofrequency Therapy After Eccentric Exercise-Induced Muscle Damage to Restore Muscle Strength and Contractile Parameters.

CONTEXT: Exercise-induced muscle damage (EIMD) is prevalent especially in sports and rehabilitation. It causes loss in skeletal muscle function and soreness. As there are no firm preventive strategies, we aimed to evaluate the preventive efficacy of nonthermal 448-kHz capacitive resistive monopolar radiofrequency (CRMRF) therapy after eccentric bouts of EIMD response in knee flexors. DESIGN: Twenty-nine healthy males (age: 25.2 [4.6] y) were randomized in control group (CG; n = 15) and experimental group (EG; n = 14) where EG followed 5 daily 448-kHz CRMRF therapies. All assessments were performed at baseline and post EIMD (EIMD + 1, EIMD + 2, EIMD + 5, and EIMD + 9 d). We measured tensiomyography of biceps femoris and semitendinosus to calculate contraction time, the maximal displacement and the radial velocity of contraction, unilateral isometric knee flexors maximal voluntary contraction torque, and rate of torque development in first 100 milliseconds. RESULTS: Maximal voluntary contraction torque and rate of torque development in first 100 milliseconds decreased more in CG than in EG and recovered only in EG. Biceps femoris contraction time increased only in CG (without recovery), whereas in semitendinosus contraction time increased in EG (only at EIMD + 1) and in CG (without recovery). In both muscles, tensiomyographic maximal displacement decreased in EG (in EIMD + 1 and EIMD + 2) and in CG (without recovery). Furthermore, in both muscles, radial velocity of contraction decreased in EG (from EIMD + 1 until EIMD + 5) and in CG (without recovery). CONCLUSION: The study shows beneficial effect of CRMRF therapy after inducing EIMD in skeletal muscle strength and contractile parameters in knee flexors.

Sarcopenia parameters in active older adults - an eight-year longitudinal study.

BACKGROUD: Sarcopenia is a common skeletal muscle syndrome that is common in older adults but can be mitigated by adequate and regular physical activity. The development and severity of sarcopenia is favored by several factors, the most influential of which are a sedentary lifestyle and physical inactivity. The aim of this observational longitudinal cohort study was to evaluate changes in sarcopenia parameters, based on the EWGSOP2 definition in a population of active older adults after eight years. It was hypothesized that selected active older adults would perform better on sarcopenia tests than the average population. METHODS: The 52 active older adults (22 men and 30 women, mean age: 68.4 ± 5.6 years at the time of their first evaluation) participated in the study at two time points eight-years apart. Three sarcopenia parameters were assessed at both time points: Muscle strength (handgrip test), skeletal muscle mass index, and physical performance (gait speed), these parameters were used to diagnose sarcop0enia according to the EWGSOP2 definition. Additional motor tests were also performed at follow-up measurements to assess participants' overall fitness. Participants self-reported physical activity and sedentary behavior using General Physical Activity Questionnaire at baseline and at follow-up measurements. RESULTS: In the first measurements we did not detect signs of sarcopenia in any individual, but after 8 years, we detected signs of sarcopenia in 7 participants. After eight years, we detected decline in ; muscle strength (-10.2%; p < .001), muscle mass index (-5.4%; p < .001), and physical performance measured with gait speed (-28.6%; p < .001). Similarly, self-reported physical activity and sedentary behavior declined, too (-25.0%; p = .030 and - 48.5%; p < .001, respectively). CONCLUSIONS: Despite expected lower scores on tests of sarcopenia parameters due to age-related decline, participants performed better on motor tests than reported in similar studies. Nevertheless, the prevalence of sarcopenia was consistent with most of the published literature. TRIAL REGISTRATION: The clinical trial protocol was registered on ClinicalTrials.gov, identifier: NCT04899531.

Diagnostic accuracy of Tensiomyography parameters for monitoring peripheral neuromuscular fatigue.

The diagnostic accuracy of tensiomyography (TMG) parameters compared to the gold standard in neuromuscular fatigue evaluation using voluntary and electrically induced muscle activation is unclear. This study aimed to investigate the diagnostic accuracy of TMG parameters to detect individual changes after interventions that were designed to induce central or peripheral fatigue. Nineteen males (age: 32.2 ± 9.3 years) performed two interventions, consisting of maintaining 25% of maximal voluntary contraction (MViC25%) and a 30 s all-out cycling test (Wingate), respectively. TMG parameters, maximum voluntary contraction (PtMViC), voluntary activation (VA%) and electrically elicited double twitches (Dtw) were assessed on the knee extensors before (PRE), one minute (POST) and seven minutes after (POST7) the intervention. The diagnostic accuracy (AUC) of TMG parameters were evaluated in comparison to two criteria measures (PtMViC and Dtw). RM ANOVA revealed a significant interaction between the effects of intervention and time on VA% (p = 0.001) and Dtw (p < 0.001) but not for PtMViC (p = 0.420). AUC showed that TMG parameters had a good ability in detecting muscular fatigue assessed by Dtw but not by PtMViC. The results of the current study suggest that TMG parameters can be used to monitor peripheral neuromuscular fatigue.

Interleukin-18 Is a Potential Biomarker Linking Dietary Fatty Acid Quality and Insulin Resistance: Results from a Cross-Sectional Study in Northern Italy.

Dietary lipids are pivotal in modulating metabolic inflammation. Among the inflammatory mediators characterizing metabolic inflammation, interleukin 18 (IL-18) has been consistently associated with obesity and insulin resistance. This study aims to evaluate whether the quality of lipid intake impacts upon IL-18 plasma levels and the implications on insulin resistance computed by the homeostatic model assessment for insulin resistance (HOMA-IR). Using a cross-sectional design, this study confirmed that IL-18 correlated positively with insulin resistance and individuals with a HOMA-IR ≥ 2.5 displayed higher circulating IL-18 levels compared with their insulin-sensitive counterparts. In terms of the effect of the quality of dietary lipids on IL-18 circulating levels, the ratio between monounsaturated, omega-3, polyunsaturated and saturated fatty acids as well as the intake of eicosapentaenoic and docosahexaenoic acids correlated negatively with IL-18. Despite this, IL-18 circulating levels, but not dietary fatty acid quality, predicted insulin resistance. Nevertheless, the ratio between omega 3 and saturated fatty acids was a predictor of IL-18 plasma levels. Thus, the downregulation of IL-18 may underpin, at least partially, the beneficial metabolic effects of substituting omega 3 for saturated fatty acids with this cytokine potentially representing a biomarker linking dietary lipids and metabolic outcomes.

Sarcopenia, obesity, and their association with selected behavioral factors in active older adults.

Introduction: The number of obese people in the world is increasing, as is the number of sarcopenic people among the older adults. Although both states are concerning, they can be positively influenced by selected behavioral factors such as adequate nutrition and physical activity. We were interested in the prevalence of sarcopenic obesity in active older people and the influence of behavioral factors on this phenomenon. Methods: The study included 38 older adults (21 women) with a mean age of 75.3 ± 5.0 years. Sarcopenic parameters were determined with different tests: Handgrip Test, Chair Stand Test, Gait Speed, Timed Up and Go Test, and Short Physical Performance Battery. Body composition was measured by dual-energy x-ray absorptiometry. Physical activity level was measured using accelerometers, and nutritional status was assessed using the Mini-Nutritional Assessment and MEDLIFE Index questionnaire. Results: Of all included active participants (the average number of steps per day was 8,916 ± 3,543), 47.4% of them were obese. Of all included women, 52.4% were obese. Sarcopenic obesity was found in three (7.9%) participants. Nutritional status correlated with strength of lower extremities and physical performance tests (gait speed, Timed Up and Go Test and Short Physical performance battery). Higher number of steps per day positively correlates with physical performance. Discussion: Interestingly, we did not find any correlation between the main obesity parameter such as percent body fat or body mass index (and thus sarcopenic obesity) and any of the selected behavioral factors (physical activity, sedentary behavior, or dietary habits). In conclusion, reaching the recommended levels of physical activity in older adults may not be sufficient to prevent the occurrence of obesity and sarcopenic obesity.

Impact of 10-day bed rest on serum levels of irisin and markers of musculoskeletal metabolism.

The bed rest (BR) is a ground-based model to simulate microgravity mimicking skeletal-muscle alterations as in spaceflight. Molecular coupling between bone and muscle might be involved in physiological and pathological conditions. Thus, the new myokine irisin and bone-muscle turnover markers have been studied during and after 10 days of BR. Ten young male individuals were subjected to 10 days of horizontal BR. Serum concentrations of irisin, myostatin, sclerostin, and haptoglobin were assessed, and muscle tissue gene expression on vastus lateralis biopsies was determined. During 10-days BR, we observed no significant fluctuation levels of irisin, myostatin, and sclerostin. Two days after BR (R+2), irisin serum levels significantly decreased while myostatin, sclerostin, and haptoglobin were significantly increased compared with BR0. Gene expression of myokines, inflammatory molecules, transcription factors, and markers of muscle atrophy and senescence on muscle biopsies were not altered, suggesting that muscle metabolism of young, healthy subjects is able to adapt to the hypomobility condition during 10-day BR. However, when subjects were divided according to irisin serum levels at BR9, muscle ring finger-1 mRNA expression was significantly lower in subjects with higher irisin serum levels, suggesting that this myokine may prevent the triggering of muscle atrophy. Moreover, the negative correlation between p21 mRNA and irisin at BR9 indicated a possible inhibitory effect of the myokine on the senescence marker. In conclusion, irisin could be a prognostic marker of hypomobility-induced muscle atrophy, and its serum levels could protect against muscle deterioration by preventing and/or delaying the expression of atrophy and senescence cellular markers.

Effects of Meditation on Cardiovascular and Muscular Responses in Patients during Cardiac Rehabilitation: A Randomized Pilot Study.

BACKGROUND: Cardiovascular diseases are the world's number one cause of death, with exceeding psychosocial stress load being considered a major risk factor. A stress management technique that has repeatedly shown positive effects on the cardiovascular system is the Transcendental Meditation (TM) technique. The present pilot study aimed to investigate the potential effect of TM on the recovery of cardiac patients. OBJECTIVES: We hypothesized that practicing TM in patients undergoing a 4-week cardiac rehabilitation program augments the recovery of cardiovascular parameters and reduces skeletal muscle tone after rehabilitation. METHODS: Twenty cardiac patients were recruited and randomly assigned to either the control or the TM group. Cardiovascular parameters were assessed with the Task Force Monitor (TFM) and skeletal muscle contractile properties by Tensiomyography during a sit-stand test, performed at the beginning and end of a 4-week in-patient rehabilitation program. RESULTS: Systolic blood pressure (SBP) was significantly lower after 4 weeks of cardiac rehabilitation, while the RR-interval (RRI) significantly increased. At the skeletal muscle level, the contraction time and maximal displacement increased, though only in the gastrocnemius medialis and biceps femoris muscles and not in vastus lateralis. Group interactions were not observed for hemodynamic parameters nor for muscle contractile properties. DISCUSSION: Although significant improvements in hemodynamic and muscular parameters were observed after 4 weeks of rehabilitation, we could not provide evidence that TM improved rehabilitation after 4 weeks. TM may unfold its effects on the cardiovascular system in the longer term. Hence, future studies should comprise a long-term follow-up.

Irisin Attenuates Muscle Impairment during Bed Rest through Muscle-Adipose Tissue Crosstalk.

The detrimental effect of physical inactivity on muscle characteristics are well known. Irisin, an exercise-induced myokine cleaved from membrane protein fibronectin type III domain-containing protein-5 (FNDC5), mediates at least partially the metabolic benefits of exercise. This study aimed to assess the interplay between prolonged inactivity, circulating irisin, muscle performance, muscle fibers characteristics, as well as the FNDC5 gene expression (FNDC5ge) in muscle and adipose tissue among healthy subjects. Twenty-three healthy volunteers were tested before and after 14 days of Bed Rest, (BR). Post-BR circulating levels of irisin significantly increased, whereas body composition, muscle performance, and muscle fiber characteristics deteriorated. Among the subjects achieving the highest post-BR increase of irisin, the lowest reduction in maximal voluntary contraction and specific force of Fiber Slow/1, the highest increase of FNDC5ge in adipose tissue, and no variation of FNDC5ge in skeletal muscle were recorded. Subjects who had the highest FNDC5ge in adipose tissue but not in muscle tissue showed the highest circulating irisin levels and could better withstand the harmful effect of BR.

Decomposition of tensiomyogram and comparison with torque twitch responses after post-activation potentiation.

OBJECTIVES: This study evaluates the effect of post-activation potentiation (PAP) after 5x5s maximal voluntary isometric contractions (activation stimulus, AS) on tensiomyography (TMG) and torque twitch contractile parameters of vastus lateralis (VL) and medialis (VM), respectively. Further, we validated the decomposition of TMG response to separate responses of three fiber types. METHODS: 15 healthy individuals participated in this study (40% women; age 19±2.3 years). A decomposition of VL TMG response was done after optimal fitting of three exponential curves. RESULTS: We found main effects in contraction time (Tc) for muscle, method and time. Furthermore, we found interactions between muscle*method, method*time and muscle*method*time. Compared to PRE AS, we found shorter TMG Tc in VL and VM during the first two minutes after AS. Torque Tc remained unchanged in VL, while it increased in VM within 30 seconds after AS. A decomposition of VL TMG response confirmed PAP effects being present only in decomposed type IIb muscle fibers. CONCLUSION: The TMG is a sensitive method to detect PAP effects with a sensor mounted directly above the muscle belly. After the decomposition of the TMG signal to three separate muscle fiber phenotypes, we provided a non-invasive insight in the contribution of each muscle fiber phenotype to the PAP of the whole muscle.

Does an active lifestyle matter? A longitudinal study of physical activity and health-related determinants in older adults.

Introduction: It is well-known that regular physical activity, and thus an active lifestyle, has positive effects on aging and general wellbeing. However, the question remains as to whether regular or increased physical activity can improve self-perception of health status and quality of life in older adults. Methods: We conducted a longitudinal study on a group of active older adults between 2013 and 2021. At baseline, i.e., the 1st measurements (baseline), 147 participants were enrolled (mean age 68.4 ± 5.6). After 8 years, in 2021 (follow up), 52 older adults (mean age 75.9 ± 5.3 years) were measured. For the purpose of this study, we included 52 older adults participated at both time-points. For both measurements, participants reported their physical activity and sedentary behavior using the Global physical activity questionnaire (GPAQ), socio-demographic and environmental determinants, recording their self-perception in terms of overall wellbeing. Furthermore, we conducted a qualitative study using semi-structured interviews to obtain subjective data on the changes and events that may have affected physical abilities and general health over an 8-year period. Results: At the follow up, participants reported lower physical activity and sedentary behavior compared to baseline, but still met health-enhancing physical activity (HEPA) standards for total self-reported physical activity (>3,000 METmin/week). In addition, they rated their overall health (p < 0.001), physical fitness (p < 0.001), psychological wellbeing (p < 0.001) and overall quality of life (p < 0.001) as better. The qualitative data confirmed that the 8-year period involved changes in physical activity. Specifically, they have continued to carry out physical work (gardening, working in the vineyards, olive groves), but previously organized physical activities were replaced by walks in nature, which probably also influenced the reduction of sedentary behavior. Conclusion: After 8 years, as expected, participants reported a decrease in physical activity and a lower level of sedentary behavior. It appears from the interview that healthy older adults filled their days with daily tasks and found more time for walking. Individuals who were more active in the past 8 years also reported better overall health and wellbeing. Selected variables correlated with an active lifestyle and better perceptions of quality of life.

The reliability, validity and usefulness of the 30-15 intermittent fitness test for cardiorespiratory fitness assessment in military personnel.

The objectives of this study were to investigate the reliability, validity, and usefulness of the 30-15 intermittent fitness test (30-15IFT) in soldiers. The 34 infantry members of the Slovenian armed forces were recruited as participants. Participants performed the continuous incremental treadmill test (TR), a 2-mile run (2MR) test, and two 30-15IFT tests. Additionally, participants were divided into a highest-scoring group (HSG) and a lowest-scoring group (LSG) based on their scores on the Army Physical Fitness Test. A very high reliability ratings were observed for 30-15IFT measures, as follows: end-running speed (ERS) ERSIFT (ICC = 0.971), maximal heart rate (HRmax) HRmaxIFT (IC = 0.960), and maximal relative oxygen consumption (VO2max) VO2max-IFT (ICC = 0.975). Although 30-15IFT measures demonstrated high correlations (r = 0.695-0.930) to the same measures of TR test, ERS, HRmax and VO2max were higher in the 30-15IFT (p > 0.05). Furthermore, ERSIFT and predicted VO2maxIFT were higher in HSG compared to LSG, whereas HRmax did not differ. The results of this study show that the 30-15IFT test is a reliable, valid and useful tool for assessing cardiorespiratory fitness in the armed forces. Moreover, the ERS and predicted VO2max values derived from the 30-15IFT could be considered more sensitive markers of combat readiness than the parameters derived from the TR and 2MR tests.Trial registration number: NCT05218798.