Feasibility and effectiveness of non-linear periodized resistance training in people with COPD

Chronic obstructive pulmonary disease (COPD) is a leading cause of death
worldwide. It is estimated that over 500 000 patients suffer from this disease
in the Netherlands. Although COPD is primarily a disease of the respiratory
system, a common secondary consequence is quadriceps muscle dysfunction, that
is, reduced muscle strength and/or endurance.
Limb muscle dysfunction is a heterogeneous process in patients with COPD but
this is rarely considered in the exercise training prescription. Resistance
training (RT) is the best available means to improve limb muscle function in
patients with COPD. However, the optimal RT prescription for people with COPD
with regard to improving either limb muscle strength or endurance has yet to be
determined. Current guidelines for RT in COPD mainly focus on improving muscle
strength which only reflects one aspect of limb muscle function and does not
address the issue of reduced muscle endurance. Periodized resistance training,
which represents a planned variation of RT variables (e.g., volume, intensity),
is one strategy that could be used to target muscle strength as well as muscle
endurance within the same exercise regimen. In patients with COPD, nonlinear
periodized exercise training has resulted in greater effects in exercise
capacity as well as quality of life in comparison to traditional exercise
training. However, the potential effect of utilizing the concept of nonlinear
periodized resistance training (NLPRT) in patients with COPD is less
investigated.

The primary objective is to compare the effect of NLPRT with traditional
non-periodized RT (TRT) on isotonic upper and lower limb muscle strength and
limb muscle endurance in patients with COPD.The secondary objectives are to
compare the effect of NLPRT and TRT on functional performance, isometric
quadriceps muscle strength and endurance, quality of life, dyspnea, and the
proportion of responders for each of these variables.

This study is a prospective, randomized, controlled, parallel two-group trial.
Assessments are made in week 1 and 10. Measurements for this research project
are part of routine clinical practice: standard spirometry, bio-impedance
analysis, physical activity, functional exercise capacity (incremental and
endurance shuttle walk tests), muscle strength and endurance.

Participants will be randomized to either NLPRT or TRT of leg press, shoulder
flexion, calf press and chest press exercises (3 times per week for 8 weeks).
The following will be similar for both the NLPRT and the TRT group.
1. All exercises will be performed using training equipment available at each
participating center. Leg press, chest press and calf press exercises will be
performed using available weight machines and the shoulder flexion exercise
will be performed using free weights.
2. Exercise order will be pre-determined: 1) leg press, 2) shoulder flexion, 3)
calf press and 4) chest press. This exercise order will be used in order to
alternate between lower and upper limb exercises and between multiple- and
single-joint exercises. All exercises will be performed bilateral.
3. Rest between exercises will be standardized to 4 minutes and all exercises
will be performed using dynamic repetitions with both concentric and eccentric
muscle actions. The speed of motion in each exercise will be controlled by the
breathing of the participant, we expect a moderate exercise velocity i.e.,
1-2:1-2 seconds in the concentric and the eccentric phase respectively.
4. All sessions will be supervised and conducted by local professionals.
5. Each session will span approximately 60 minutes including a mandatory 5
minute rest before and after the training sessions. During this time, Borg
dyspnea and general fatigue ratings, oxygen saturation and heart rate will be
collected.
6. Borg dyspnea, limb muscle fatigue and exertion ratings, the later defined as
*how heavy the exercise felt*, will be collected immediately after each set of
exercise.
7. Exercise volume for each training session = (number of repetitions per set *
sets per exercise * exercises per session) will be reported.
8. New 1 RM and multiple RM tests will be performed 3 times during the 8-week
intervention period (after session 5, 10 and 15) in order to optimize exercise
loadings. If a RM test will be lower than the prior RM a new test will be
performed prior to the next training session to minimize impact of alterations
in daily fitness.
9. No general or specific warm-up will be performed prior to commencing limb
muscle endurance protocol in the NLPRT group but a specific warm-up set of 15
repetitions using a load corresponding to 30% of 1RM prior to all strength
protocols within the NLPRT and TRT group will be performed.

The risks on any undesirable side effects of this study are very low, since
tests and interventions are part of regular care tests. The benefits of the
study are high, because the results from this study will optimize exercise
training in patients with COPD.