Effects of training at mild exercise intensities on quadriceps muscle energy metabolism in patients with chronic obstructive pulmonary disease

Effects of different exercise regimens on prognosis of patients with chronic obstructive pulmonary disease: a systematic reviews and meta-analysis

INTRODUCTION

Skeletal muscle dysfunction is a significant factor contributing to exercise limitation in patients with chronic obstructive pulmonary disease (COPD). Although exercise training is often recommended to enhance patient outcomes, there continues to be ongoing debate regarding its exact effects.

OBJECTIVE

The aim of this study is to evaluate the effectiveness of endurance exercise, strength training and combined exercise on cardiorespiratory fitness (including maximal oxygen uptake, maximal minute ventilation, and the 6-minute walk test), strength of lower limbs (measured by leg press), and quality of life (using the COPD Assessment Test) in patients with COPD. By conducting a systematic review and meta-analysis of randomized controlled trials (RCTs), our objective is to provide tailored training methods and intensity recommendations for patients with COPD in order to improve their quality of life.

METHODS

The meta-analysis included 10 randomized controlled trials (RCTs) of exercise rehabilitation programs involving 180 patients with COPD that were retrieved from electronic databases (PubMed, Cochrane Library, and Embase). Two reviewers independently assessed the topical relevance, trial quality, and extracted data for the meta-analysis.

RESULTS

Meta-analysis showed that primary outcomes representing exercise endurance were elevated under different exercise interventions compared to pre-test, such as maximal oxygen uptake (VO2max (ml/kg/min)) [SMD = 0.40, 95% CI (0.15, 0.64)] and the 6-min walk test (6MWT) [MD = 33.90, 95% CI (25.25, 42.55)], and primary outcomes representing strength also increased, such as leg press (1RM) [MD = 24.59, 95% CI (16.08, 33.11)], while secondary outcomes such as assessments of life such as the COPD Assessment Test (CAT) recovered [MD = 2.51, 95% CI (2.01, 3.00)], with all differences being statistically significant (p < 0.05). However, Maximum minute ventilation (VEmax (L)) [MD = 0.91, 95%CI (3.61, 5.43)] was not statistically significant (p > 0.05) when compared with the post-test data. The sensitivity test data were stable, and the results were reliable. We subgrouped the data from different types of exercise interventions and found that different types of exercise affected the experimental results.

CONCLUSION

Exercise interventions have a positive effect on the treatment of patients with COPD, significantly improving functional capacity, aerobic capacity, and exercise tolerance, but they should be individualized and developed according to the patient's condition to achieve the best therapeutic effect.

Effects of different traditional Chinese exercises on pulmonary function in patients with stable chronic obstructive pulmonary disease: a network meta-analysis

OBJECTIVE

Traditional Chinese exercises (Taichi, Wuqinxi, Liuzijue, and Baduanjin) are considered effective alternative treatments for improving symptoms in the stable phase of COPD. However, the most effective exercise remains unknown. This study compared the effectiveness of different traditional Chinese exercises on pulmonary function in patients with stable chronic obstructive pulmonary disease (COPD) using a network meta-analysis.

METHODS

From database establishment until September 2023, eligible randomized controlled trials (RCTs) were searched. Two reviewers performed the risk of bias assessment of the included studies using the Cochrane Collaboration tool, and the evidence level was suggested using the GRADE system.

RESULTS

Fifty-seven studies comprising 4294 patients were included. The results of the network meta-analysis show that Baduanjin was most effective in improving the forced expiratory volume in the first second (FEV1). However, Liuzijue significantly improved the first-second forced vital capacity percentage of expected value (FEV1%) and the ratio of the forced expiratory volume in the first second to the forced vital capacity (FEV1/FVC). The probability ranking results indicated that Liuzijue was the most effective, followed by Baduanjin, Wuqinxi, and Taichi. Subgroup analysis in conjunction with intervention duration revealed that Liuzijue had a significant advantage over other interventions for improving FEV1, FEV1%, and FEV1/FVC within 6 months and improved FEV1% and FEV1/FVC for ≥ 6 months. Moreover, Subgroup analysis based on baseline pulmonary function revealed that Liuzijue had a significant advantage over other interventions for improving FEV1% within severe and moderate groups. Finally, Subgroup analysis based on the frequency of interventions showed that Liuzijue was still more effective in improving FEV1, FEV1%, and FEV1/FVC in the ≥ three times one week.

CONCLUSION

Liuzijue was more effective than Taichi, Wuqinxi, Liuzijue, and Baduanjin in improving pulmonary function in patients with stable COPD.

Skeletal Muscle Mitochondrial Dysfunction in Chronic Obstructive Pulmonary Disease: Underlying Mechanisms and Physical Therapy Perspectives

Skeletal muscle dysfunction (SMD) is a prevalent extrapulmonary complication and a significant independent prognostic factor in patients with chronic obstructive pulmonary disease (COPD). Mitochondrial dysfunction is one of the core factors that damage structure and function in COPD skeletal muscle and is closely related to smoke exposure, hypoxia, and insufficient physical activity. The currently known phenotypes of mitochondrial dysfunction are reduced mitochondrial content and biogenesis, impaired activity of mitochondrial respiratory chain complexes, and increased mitochondrial reactive oxygen species production. Significant progress has been made in research on physical therapy (PT), which has broad prospects for treating the abovementioned potential mitochondrial-function changes in COPD skeletal muscle. In terms of specific types of PT, exercise therapy can directly act on mitochondria and improve COPD SMD by increasing mitochondrial density, regulating mitochondrial biogenesis, upregulating mitochondrial respiratory function, and reducing oxidative stress. However, improvements in mitochondrial-dysfunction phenotype in COPD skeletal muscle due to different exercise strategies are not entirely consistent. Therefore, based on the elucidation of this phenotype, in this study, we analyzed the effect of exercise on mitochondrial dysfunction in COPD skeletal muscle and the regulatory mechanism thereof. We also provided a theoretical basis for exercise programs to rehabilitate this condition.

Evaluation of Training with Elastic Bands on Strength and Fatigue Indicators in Paralympic Powerlifting

Background: Variable resistance training has recently become a component of strength and conditioning programs. Objective: This randomized counterbalanced cross-over study aimed to investigate the use of elastic bands (EB) and the traditional method (TRAD) and force indicators in a training session. Methods: 12 Paralympic athletes (age: 28.60 ± 7.60 years) participated in this three-week study. In the first week, the participants were familiarized with EB and TRAD and were tested for maximal repetition (1-RM). The research occurred in weeks 2 and 3, which included the pre-post training, during which the following measures were extracted: maximum isometric force (MIF), the peak torque (PT), rate of force development (RFD), fatigue index (FI), and time to MIF (Time). The athletes performed two tests, EB and TRAD, separated by a one-week interval. Results: Significant differences were found between the pre- and post-test for 1RM (p = 0.018, η2p = 0.412), MIF (p = 0.011, η2p = 0.415), PT (p = 0.012, η2p = 0.413), and RFD (p = 0.0002, η2p = 0.761). With the use of EB, there was a difference in RFD between TRAD before and EB after (p = 0.016, η2p = 0.761). There were significant differences in the before and after for FI between TRAD and EB (p < 0.001) and for Time (p < 0.001), indicating that training with the use of elastic bands promotes overload, characterized by increased fatigue and decreased strength. Conclusions: Training with EB did not decrease 1RM, PT, MIF or RFD, however, there was an increase in fatigue and time to reach MIF when compared to the method with fixed resistance.

Locomotor Muscles in COPD: The Rationale for Rehabilitative Exercise Training

Exercise training as part of pulmonary rehabilitation is arguably the most effective intervention to improve tolerance to physical exertion in patients with chronic obstructive pulmonary disease (COPD). Owing to the fact that exercise training has modest effects on exertional ventilation, operating lung volumes and respiratory muscle performance, improving locomotor muscle structure and function are key targets for pulmonary rehabilitation in COPD. In the current concise review, we initially discuss whether patients’ muscles are exposed to deleterious factors. After presenting corroboratory evidence on this regard (e.g., oxidative stress, inflammation, hypoxemia, inactivity, and medications), we outline their effects on muscle macro- and micro-structure and related functional properties. We then finalize by addressing the potential beneficial consequences of different training strategies on these muscle-centered outcomes. This review provides, therefore, an up-to-date outline of the rationale for rehabilitative exercise training approaches focusing on the locomotor muscles in this patient population.

Effects of long-term home-based Liuzijue exercise combined with clinical guidance in elderly patients with chronic obstructive pulmonary disease

Purpose

This study was designed to investigate the effects of long-term home-based Liuzijue exercise combined with clinical guidance in elderly patients with chronic obstructive pulmonary disease (COPD).

Methods

Forty patients with COPD at stages II–III of the Global Initiative for Chronic Obstructive Lung Disease were enrolled. The subjects were randomly allocated to the Liuzijue exercise group (LG) or control group (CG) in a 1:1 ratio. Participants in the LG performed six Liuzijue training sessions, including 4 days at home and 2 days in the hospital with clinical guidance for 60 minutes/day for 6 months. Participants in the CG conducted no exercise intervention. In addition, lung function test, 6-minute walking test (6MWT), 30-second sit-to-stand test (30 s SST), and the St George’s Respiratory Questionnaire (SGRQ) were conducted at the baseline and at the end of the intervention.

Results

Thirty-six patients completed the study. The patients’ lung function improved significantly (p < 0.05) in the LG as well as the 6MWT, 30 s SST, and SGRQ score (p < 0.01). While the SGRQ total score, activity, and impact scores increased significantly (p < 0.05) in the CG. In addition, there were significant differences between the groups (p < 0.01) in regard to the values of forced expiratory volume in 1 second as a percentage of the predicted volume, 6MWT, 30 s SST, and SGRQ.

Conclusions

Long-term home-based Liuzijue exercise combined with clinical guidance can effectively improve the pulmonary function, exercise capacity, and quality of life of elderly patients with moderate to severe COPD.

Can muscle protein metabolism be specifically targeted by exercise training in COPD?

Patients with stable chronic obstructive pulmonary disease (COPD) frequently exhibit unintentional accentuated peripheral muscle loss and dysfunction. Skeletal muscle mass in these patients is a strong independent predictor of morbidity and mortality. Factors including protein anabolism/catabolism imbalance, hypoxia, physical inactivity, inflammation, and oxidative stress are involved in the initiation and progression of muscle wasting in these patients. Exercise training remains the most powerful intervention for reversing, in part, muscle wasting in COPD. Independently of the status of systemic or local muscle inflammation, rehabilitative exercise training induces up-regulation of key factors governing skeletal muscle hypertrophy and regeneration. However, COPD patients presenting similar degrees of lung dysfunction do not respond alike to a given rehabilitative exercise stimulus. In addition, a proportion of patients experience limited clinical outcomes, even when exercise training has been adequately performed. Consistently, several reports provide evidence that the muscles of COPD patients present training-induced myogenic activity limitation as exercise training induces a limited number of differentially expressed genes, which are mostly associated with protein degradation. This review summarises the nature of muscle adaptations induced by exercise training, promoted both by changes in the expression of contractile proteins and their function typically controlled by intracellular signalling and transcriptional responses. Rehabilitative exercise training in COPD patients stimulates skeletal muscle mechanosensitive signalling pathways for protein accretion and its regulation during muscle contraction. Exercise training also induces synthesis of myogenic proteins by which COPD skeletal muscle promotes hypertrophy leading to fusion of myogenic cells to the myofiber. Understanding of the biological mechanisms that regulate exercise training-induced muscle growth and regeneration is necessary for implementing therapeutic strategies specifically targeting myogenesis and hypertrophy in these patients.

Changes in lower limb muscle function and muscle mass following exercise-based interventions in patients with chronic obstructive pulmonary disease: A review of the English-language literature

Chronic obstructive pulmonary disease (COPD) patients often experience lower limb muscle dysfunction and wasting. Exercise-based training has potential to improve muscle function and mass, but literature on this topic is extensive and heterogeneous including numerous interventions and outcome measures. This review uses a detailed systematic approach to investigate the effect of this wide range of exercise-based interventions on muscle function and mass. PUBMED and PEDro databases were searched. In all, 70 studies (n = 2504 COPD patients) that implemented an exercise-based intervention and reported muscle strength, endurance, or mass in clinically stable COPD patients were critically appraised. Aerobic and/or resistance training, high-intensity interval training, electrical or magnetic muscle stimulation, whole-body vibration, and water-based training were investigated. Muscle strength increased in 78%, muscle endurance in 92%, and muscle mass in 88% of the cases where that specific outcome was measured. Despite large heterogeneity in exercise-based interventions and outcome measures used, most exercise-based trials showed improvements in muscle strength, endurance, and mass in COPD patients. Which intervention(s) is (are) best for which subgroup of patients remains currently unknown. Furthermore, this literature review identifies gaps in the current knowledge and generates recommendations for future research to enhance our knowledge on exercise-based interventions in COPD patients.

Restrictions in ATP diffusion within sarcomeres can provoke ATP-depleted zones impairing exercise capacity in chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by the inability of patients to sustain a high level of ventilation resulting in perceived exertional discomfort and limited exercise capacity of leg muscles at average intracellular ATP levels sufficient to support contractility.

METHODS

Myosin ATPase activity in biopsy samples from healthy and COPD individuals was implemented as a local nucleotide sensor to determine ATP diffusion coefficients within myofibrils. Ergometric parameters clinically measured during maximal exercise tests in both groups were used to define the rates of myosin ATPase reaction and aerobic ATP re-synthesis. The obtained parameters in combination with AK- and CK-catalyzed reactions were implemented to compute the kinetic and steady-state spatial ATP distributions within control and COPD sarcomeres.

RESULTS

The developed reaction-diffusion model of two-dimensional sarcomeric space identified similar, yet extremely low nucleotide diffusion in normal and COPD myofibrils. The corresponding spatio-temporal ATP distributions, constructed during imposed exercise, predicted in COPD sarcomeres a depletion of ATP in the zones of overlap between actin and myosin filaments along the center axis at average cytosolic ATP levels similar to healthy muscles.

CONCLUSIONS

ATP-depleted zones can induce rigor tension foci impairing muscle contraction and increase a risk for sarcomere damages. Thus, intra-sarcomeric diffusion restrictions at limited aerobic ATP re-synthesis can be an additional risk factor contributing to the muscle contractile deficiency experienced by COPD patients.

GENERAL SIGNIFICANCE

This study demonstrates how restricted substrate mobility within a cellular organelle can provoke an energy imbalance state paradoxically occurring at abounding average metabolic resources.

Changes in structural and metabolic muscle characteristics following exercise-based interventions in patients with COPD: a systematic review

Patients with COPD suffer from lower-limb muscle dysfunction characterized by lower muscle oxidative capacity and muscle mass. Exercise-based training is expected to attenuate lower-limb intramuscular characteristics, but a detailed systematic approach to review the available evidence has not been performed yet. PUBMED and PEDro databases were searched. Twenty-five studies that implemented an exercise-based training program (aerobic and/or resistance training, high intensity interval training, electrical or magnetic stimulation) and reported muscle biopsy data of patients with COPD were critically appraised. The coverage of results includes changes in muscle structure, muscle protein turnover regulation, mitochondrial enzyme activity, oxidative and nitrosative stress, and inflammation after exercise-based training interventions. Study design and training modalities varied among studies, which partly explains the observed heterogeneous response in muscle characteristics. Gaps in the current knowledge are identified and recommendations for future research are made to enhance our knowledge on exercise training effects in patients with COPD.

Exercise training with negative pressure ventilation improves exercise capacity in patients with severe restrictive lung disease: a prospective controlled study

Background

Exercise training is of benefit for patients with restrictive lung disease. However, it tends to be intolerable for those with severe disease. We examined whether providing ventilatory assistance by using negative pressure ventilators (NPV) during exercise training is feasible for such patients and the effects of training.

Methods

36 patients with restrictive lung disease were prospectively enrolled for a 12-week multidisciplinary rehabilitation program. During this program, half of them (n:18; 60.3 ± 11.6 years; 6 men; FVC: 32.5 ± 11.7% predicted ) received regular sessions of exercise training under NPV, whilst the 18 others (59.6 ± 12.3 years; 8 men; FVC: 37.7 ± 10.2% predicted) did not. Exercise capacity, pulmonary function, dyspnea and quality of life were measured. The primary endpoint was the between-group difference in change of 6 minute-walk distance (6MWD) after 12 weeks of rehabilitation.

Results

All patients in the NPV-exercise group were able to tolerate and completed the program. The between-group differences were significantly better in the NPV-exercise group in changes of 6MWD (34.1 ± 12.7 m vs. -32.5 ± 17.5 m; P = 0.011) and St George Score (−14.5 ± 3.6 vs. 11.8 ± 6.0; P < 0.01). There was an improvement in dyspnea sensation (Borg’s scale, from 1.4 ± 1.5 point to 0.8 ± 1.3 point, P = 0.049) and a small increase in FVC (from 0.85 ± 0.09 L to 0.91 ± 0.08 L, P = 0.029) in the NPV-exercise group compared to the control group.

Conclusion

Exercise training with NPV support is feasible for patients with severe restrictive lung diseases, and improves exercise capacity and health-related quality of life.

Nutritional targets to enhance exercise performance in chronic obstructive pulmonary disease

PURPOSE OF REVIEW

This review presents current knowledge regarding the rationale and efficacy of nutrition as an ergogenic aid to enhance the effects of exercise and training in chronic obstructive pulmonary disease (COPD).

RECENT FINDINGS

Altered body composition and skeletal muscle dysfunction in COPD suggest that exercise capacity can be targeted via several metabolic routes. Muscle metabolic alterations in COPD include a reduced oxidative metabolism and enhanced susceptibility for oxidative stress. Muscle wasting may be associated with deficiencies of vitamin D and low branched-chain amino acid levels. Exercise training is of established benefit in COPD but clear-cut clinical trial evidence to support the performance enhancing effect of nutritional intervention is lacking. One randomized controlled trial suggested that augmentation of training with polyunsaturated fatty acids may improve exercise capacity. Conflicting results are reported on dietary creatine supplementation in patients with COPD receiving pulmonary rehabilitation and results from acute intervention studies do not directly imply long-term effects of glutamate or glutamine supplementation as an ergogenic aid in COPD. Recent data indicate that not only muscle but also visceral fat may be an important additional target for combined nutrition and exercise intervention in COPD to improve physical performance and decrease cardiometabolic risk.

SUMMARY

There is a clear need for adequately powered and controlled intervention and maintenance trials to establish the role of nutritional supplementation in the enhancement of exercise performance and training and the wider management of the systemic features of the disease.