Ventilatory requirements of quadriceps resistance training in people with COPD and healthy controls

Abstract

Linzy Houchen-Wolloff,1 Carolyn J Sandland,1 Samantha L Harrison,1 Manoj K Menon,1 Mike D Morgan,1 Michael C Steiner,1 Sally J Singh1,21Centre for Exercise and Rehabilitation Science, Respiratory Biomedical Research Unit, Glenfield Hospital, Leicester, UK; 2Faculty of Health and Life Sciences, Coventry University, Coventry, UKBackground: It is proposed that resistance training (RT) does not activate the cardiopulmonary system to the same extent as whole-body exercise. This is important for patients with chronic obstructive pulmonary disease (COPD) who are ventilatory limited.Objective: The aim was to assess the ventilatory response to an isokinetic quadriceps RT program in people with COPD and healthy controls.Design: Observational.Registration number: ISRCTN22764439.Setting: Outpatient, university teaching hospital.Participants and outcome measures: People with COPD (n=14) and healthy controls (n=11) underwent breath-by-breath analysis of their ventilation during an RT session (five sets of 30 maximal knee extensions at 180°/sec). Subjects performed a maximal cycle ergometry test (CET) at baseline. Peak ventilation (VE; L/min) and oxygen consumption (VO2; mL/kg/min) were collected. The same system measured VO2 and VE during the RT session. Parameters are presented as a percentage of the maximal CET. Isokinetic workload, symptom scores, heart rate (HR), and oxygen saturation were documented post-training.Results: People with COPD worked at higher percentages of their maximal capacity than controls (mean range between sets 1–5 for VO2 =49.1%–60.1% [COPD], 45.7%–51.43% [controls] and for VE =57.6%–72.2% [COPD], 49.8%–63.6% [controls]), although this was not statistically significant (P>0.1 in all cases). In absolute terms, the difference between groups was only significant for actual VO2 on set 2 (P<0.05). Controls performed more isokinetic work than patients with COPD (P<0.05). Median Borg symptom scores after RT were the same in both groups (3 breathlessness, 13 exertion), no de-saturation occurred, and both groups were training at ≥65% of their maximum HR.Conclusion: No statistically significant differences were found between people with COPD and healthy controls for VO2 and VE achieved during training. The symptoms associated with training were within acceptable limits.Keywords: exercise, ventilation, strength training, resistance training