Muscular performance decreases with increasing complexity of resistance exercises in subjects with chronic obstructive pulmonary disease

Abstract

Chronic obstructive lung disease (COPD) is associated with impaired muscle functions in addition to the impaired cardiopulmonary capacity inherent to the disease.The purpose of this study was to compare muscular performance between COPD subjects (COPD, n = 11, GOLD grade II/III; FEV 1 = 53 ± 14% predicted; 61 ± 7 years) and healthy controls (HC, n = 12, 66 ± 8 years) in three resistance exercises with different complexity: (a) one-legged knee extension (1KE), and (b) one-and (c) twolegged leg press (1LP and 2LP, respectively). For each exercise, muscular performance was defined as repetitions to exhaustion at 60% of one-repetition maximum or overall exercise volume, calculated as the sum of three exercise sets. In HC, muscular performance increased progressively with increasing physiological complexity: 1KE < 1LP < 2LP. Using 1KE as reference value, muscular performance increased by 1.9 (repetitions) or 4.6-fold (volume) in 1LP and 3.1 or 7.1-fold in 2LP. In COPD, similar increases occurred going from 1KE to 1LP (1.9 or 4.4-fold change), but not from 1LP to 2LP, where no further increase occurred. In conclusion, in COPD, performance is impaired in exercises involving larger amounts of muscle mass (>1LP), advocating utilization of one-legged resistance protocols for rehabilitation purposes. K E Y W O R D Scardiorespiratory capacity, chronic obstructive lung disease, muscular performance, resistance training, strength training, unilateral training How to cite this article: Mølmen KS, Evensen Thy E, Thallaug Dalane S, Ellefsen S, Falch GS. Muscular performance decreases with increasing complexity of resistance exercises in subjects with chronic obstructive pulmonary disease. Transl Sports Med.

Chronic obstructive pulmonary disease does not impair responses to resistance training

“…Overall, COPD showed marked and hitherto unrecognized responsiveness to resistance training in respect of improvements in muscle strength, muscle mass, muscle quality and one-legged endurance performance, contradicting previous suggestions of a negative impact of co-morbidities such as low cardiorespiratory fitness and chronic low-grade systemic inflammation [ 8 , 24 ]. Indeed, a more severe COPD diagnosis was associated with larger increases in muscle mass and muscle strength improvements.…”

“…Of note, the unilateral resistance-training design was arguably supportive for the pronounced resistance-training effects in COPD participants. By reducing cardiorespiratory demand, and thus facilitating higher degrees of muscle activation and muscle mass-specific intensities during exercise compared to conventional two-legged resistance exercise [ 24 ] this seems to translate into larger functional improvements for this population [ 16 ].…”

“…For each exercise, all three sets for one leg were conducted before the other leg was exercised. This unilateral training protocol served two purposes: i) to circumvent issues relating to conduction of training with two-legged exercises in COPD [ 24 ] and ii) to investigate the relative efficacy of two different training modalities (10RM vs 30RM). Exercises and sets were separated by ~ 2 min of rest, with individual adjustments being made whenever participants needed a longer rest period.…”

Chronic Obstructive Pulmonary Disease Does Not Impair Responses to Resistance Training

“…COPD thus showed marked and hitherto unrecognized responsiveness to resistance training, contradicting previous suggestions of a negative impact of co-morbidities such as low cardiorespiratory fitness and chronic low-grade systemic inflammation. 8,38…”

“…COPD thus showed marked and hitherto unrecognized responsiveness to resistance training, contradicting previous suggestions of a negative impact of co-morbidities such as low cardiorespiratory fitness and chronic low-grade systemic inflammation. 8,38 Insert Figure 4 around here Cycling and functional performance. COPD and Healthy showed pronounced and similarly scaled training-associated improvements in whole-body endurance performance, measured as changes from baseline, including 6-min step test performance, 1-min sit-tostand performance and maximal workload achieved during two-legged cycling ( Figure 5).…”