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

Abstract

Background

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 (VO ₂; mL/kg/min) were collected. The same system measured VO ₂ 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 VO ₂ =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 VO ₂ 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 VO ₂ and VE achieved during training. The symptoms associated with training were within acceptable limits.