RESUMO
BACKGROUND: Subjects with chronic obstructive pulmonary disease (COPD) are prone to accelerated decay of muscle strength and mass with advancing age. This is believed to be driven by disease-inherent systemic pathophysiologies, which are also assumed to drive muscle cells into a state of anabolic resistance, leading to impaired abilities to adapt to resistance exercise training. Currently, this phenomenon remains largely unstudied. In this study, we aimed to investigate the assumed negative effects of COPD for health- and muscle-related responsiveness to resistance training using a healthy control-based translational approach. METHODS: Subjects with COPD (n = 20, GOLD II-III, FEV1predicted 57 ± 11%, age 69 ± 5) and healthy controls (Healthy, n = 58, FEV1predicted 112 ± 16%, age 67 ± 4) conducted identical whole-body resistance training interventions for 13 weeks, consisting of two weekly supervised training sessions. Leg exercises were performed unilaterally, with one leg conducting high-load training (10RM) and the contralateral leg conducting low-load training (30RM). Measurements included muscle strength (nvariables = 7), endurance performance (nvariables = 6), muscle mass (nvariables = 3), muscle quality, muscle biology (m. vastus lateralis; muscle fiber characteristics, RNA content including transcriptome) and health variables (body composition, blood). For core outcome domains, weighted combined factors were calculated from the range of singular assessments. RESULTS: COPD displayed well-known pathophysiologies at baseline, including elevated levels of systemic low-grade inflammation ([c-reactive protein]serum), reduced muscle mass and functionality, and muscle biological aberrancies. Despite this, resistance training led to improved lower-limb muscle strength (15 ± 8%), muscle mass (7 ± 5%), muscle quality (8 ± 8%) and lower-limb/whole-body endurance performance (26 ± 12%/8 ± 9%) in COPD, resembling or exceeding responses in Healthy, measured in both relative and numeric change terms. Within the COPD cluster, lower FEV1predicted was associated with larger numeric and relative increases in muscle mass and superior relative improvements in maximal muscle strength. This was accompanied by similar changes in hallmarks of muscle biology such as rRNA-content↑, muscle fiber cross-sectional area↑, type IIX proportions↓, and changes in mRNA transcriptomics. Neither of the core outcome domains were differentially affected by resistance training load. CONCLUSIONS: COPD showed hitherto largely unrecognized responsiveness to resistance training, rejecting the notion of disease-related impairments and rather advocating such training as a potent measure to relieve pathophysiologies. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02598830. Registered November 6th 2015, https://clinicaltrials.gov/ct2/show/NCT02598830.
Assuntos
Doença Pulmonar Obstrutiva Crônica , Treinamento Resistido , Idoso , Estudos Transversais , Tolerância ao Exercício , Humanos , Pessoa de Meia-Idade , Força Muscular , Músculo EsqueléticoRESUMO
PURPOSE: Systemic inflammation is involved in the development of several diseases, including cardiovascular disease and type 2 diabetes. It is known that vigorous exercise affects systemic inflammation, but less is known about exercise at lower intensities. Hyperglycemia can also entail pro-inflammatory responses; however, postprandial hyperglycemia is blunted if the meal is followed by exercise. Hypotheses were: (1) moderate physical exercise acutely affects levels of C-reactive protein (CRP) and serum soluble vascular cell adhesion molecule 1 (sVCAM-1) in hyperglycemic individuals and (2) the effect depends on whether the activity is performed in a post-absorptive or postprandial state. METHODS: Twelve participants diagnosed with hyperglycemia, but not using anti-diabetic medication, underwent three test days in a randomized cross-over study; 1 control day without exercise, 1 day with 60 min of treadmill walking ending 30 min before breakfast, and 1 day with an identical bout of activity 30 min after the start of breakfast. Food intake was strictly standardized and venous blood for CRP, and sVCAM-1 analysis was sampled at standardized timepoints during the first 3.5 h after breakfast and once 24 h later. RESULTS: Merged data from the two exercise days showed that sVCAM-1 increased from baseline (4 ± 16 ng/mL) compared to the control condition (-28 ± 47 ng/mL, ES = 0.7, p = 0.024). There was no statistically significant difference in changes in sVCAM-1 levels between the two exercise test days. Exercise did not affect CRP values. CONCLUSION: Moderate exercise increases sVCAM-1 in hyperglycemic individuals, whereas it does not affect CRP.
Assuntos
Proteína C-Reativa/metabolismo , Terapia por Exercício , Exercício Físico , Hiperglicemia/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Idoso , Feminino , Humanos , Hiperglicemia/terapia , Masculino , Pessoa de Meia-Idade , Período Pós-PrandialRESUMO
Postactivation-potentiation exercise with added whole-body vibration (WBV) has been suggested as a potential way to acutely improve sprint performance. In cycling, there are many competitions and situations where sprinting abilities are important. PURPOSE: To investigate the effect of adding WBV to warm-up procedures on subsequent cycle sprint performance. METHODS: Eleven well-trained cyclists participated in the study. All cyclists performed a familiarization session before 2 separate test sessions in randomized order. Each session included a standardized warm-up followed by 1 of the following preconditioning exercises: 30 s of half-squats without WBV or 30 s of half-squats with WBV at 40 Hz. A 15-s Wingate sprint was performed 1 min after the preconditioning exercise. RESULTS: Performing preconditioning exercise with WBV at 40 Hz resulted in superior peak power output compared with preconditioning exercise without WBV (1413 ± 257 W vs 1353 ± 213 W, P = .04) and a tendency toward superior mean power output during a 15-second all-out sprint (850 ± 119 W vs 828 ± 101 W, P = .08). Effect sizes showed a moderate practical effect of WBV vs no WBV on both peak and mean power output. CONCLUSIONS: Preconditioning exercise performed with WBV at 40 Hz seems to have a positive effect on cycling sprint performance in young well-trained cyclists. This suggests that athletes can incorporate body-loaded squats with WBV in preparations to specific sprint training to improve the quality of the sprint training and also to improve sprint performance in relevant competitions.