Discussion
The HRSLE trial is, to our knowledge, the first trial investigating
the effect of high-repetitive single limb exercises
in moderate to severe COPD patients. This is a
well designed study in strict accordance with CONSORT
guidelines, which will give us the opportunity to determine
the effects of the HRSLE regimen used within this
trial. A problem in many previous exercise studies is the
lack of standardization which makes reproducibility difficult.
The comprehensive standardization in this trial
facilitates the reproducibility of this trial. There is evidence
that a higher metabolic rate is achieved by training
using a reduced simultaneous muscle mass in the
form of single limb training (that is, training using one
leg/arm at a time) in COPD patients. This is due to less
stress being placed on the respiratory system as ventilation
is reduced compared to whole body exercises
[10,81]. Previous studies indicate that single limb exercise
regimens seem more effective regarding total work
conducted during exercise compared to using a larger
amount of muscle mass [11,12]. This project will give
important information about a single limb exercise
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regimen that gives patients the opportunity to incorporate
both upper as well as lower extremity muscles within
the same exercise regimen maintaining a low simultaneous
impact on the ventilatory system. To find adjunctive
exercise strategies is of great importance to optimize
the treatment of the growing population of COPD
patients. The results of this project will most likely influence
how we treat COPD patients in the future. The
number of females with COPD is increasing but most of
the previously conducted exercise trials involve a majority
of men. It is very important to investigate if the treatment
effects differ between men and women to be able
to optimize the treatment for all patients suffering from
this troublesome disease. This RCT will contribute to
the existing knowledge regarding potential sex-related
differences in physiological response to exercise training.
Adequate resistance for each separately involved muscle
within an exercise regimen is of importance to optimize
the training effects. If we could minimize the attempts
needed to reach adequate resistance and provide accurate
resistance for each involved muscle the effects of the
exercise training could increase.