Skeletal muscle weakness is present in patients with COPD and this weakness can affect lower limb strength.
Strength training can improve muscle strength, peak work capacity and endurance time.
A combination of strength and endurance training results in greater increases in both strength and endurance than either form of training alone.
Strengthening the muscles in the lower limbs is important as these muscles are used everyday. A relationship has been shown between lower limb strength and lower limb work capacity. Having stronger lower limb muscles may help patients to perform short bursts of activity (such as getting on a bus), and may also reduce falls.
Although there is no direct comparison of fall rate between people with COPD and age-matched healthy population, previous studies suggested that people with COPD have a higher prevalence of falls (44 to 51%) (Roig et al., 2011; Beauchamp et al., 2009; Beauchamp et al., 2012)11-13 compared with community-dwelling older populations (29 to 33%).14-16 The level of balance impairment and fall rate increase further after hospitalisation in people with COPD.17 Falls can be caused by a number of risk factors such as reduced lower limb muscle strength, decreased daily physical activity and reduced standing balance capacity and these risk factors are also associated with COPD.18,19 As a result, maintaining and enhancing balance is important especially for patients with a balance deficit or those with an increased risk of falls.
The following exercises can help improve balance:
- Static and dynamic stance exercises (such as stand with eyes closed, tandem stance, one-legged stance and throw and catch ball), lower limb muscle strength training (such as sit to stand exercises and stepping up and down on a block) and gait exercises (tandem, sideway and backward walk)
- Tai Chi
Strengthening the muscles in the upper limbs is also important as these muscles are used everyday. Studies indicate that strength training for the upper limb muscles results in moderate improvements in upper limb strength.20A relationship has been shown between upper limb strength and upper limb work capacity for patients with COPD which suggests that having stronger upper limb muscles may help patients perform functional tasks (i.e. by enhancing the strength of the biceps and triceps muscles).
The studies that have examined strength training for the upper limbs have focused on the accessory muscles of inspiration and muscle groups used in everyday functional tasks. These muscles include:
- Pectoral muscles
- Latissimus dorsi
Upper limb strength training can be combined with upper limb endurance training in a comprehensive program in order to gain the benefits from both modes of training.21
Continuous or Interval Training
- Exercise may be continuous or completed in an interval format.
- Continuous training is exercise at a prescribed intensity for the duration of the exercise period.
- Interval training is brief periods of high intensity exercise alternated with short periods of recovery (either rest or low intensity exercise). The total duration of exercise at the desired intensity still needs to be completed, therefore the duration of the exercise session will be longer (accounting for rests) than if the exercise was performed continuously.
- Interval training may be preferable for patients who cannot sustain the prescribed intensity for the required duration of continuous exercise (i.e. due to severe dyspnoea, marked oxygen desaturation during exercise, signs of significant fatigue or presence of symptoms from co-morbid conditions, eg claudication pain).
- Intermittent training may be needed in patients with severe disease or those who are very deconditioned. Intermittent training is short duration continuous exercise (e.g 5 minutes) followed by a rest and repeated to build the prescribed duration.
- A training circuit can be prescribed, that includes flexibility, stretching and balancing exercises.
- Circuit training should not replace lower limb endurance training unless there are stations within the circuit that replicate endurance training (e.g. 15 minutes of cycling and 15 minutes of walking at appropriately high intensities).
- At present, there are no randomised controlled trials evaluating the effectiveness of circuit training in patients with COPD.
Warm-up and Cool-down
- Warm-up and cool-down exercises can be included in exercise training sessions.
- Flexibility, stretching and balance exercises can be included as part of the warm-up and cool-down section of each exercise session.
An adequate strengthening program can be devised with or without weight equipment. Exercises should be performed slowly and smoothly.
It is generally recommended to perform the exercises in the in the sitting position with back supported. However, in everyday life upper limb activities are often carried out in standing. Some of the exercises can be performed in standing providing the patient can perform a correct technique.
Examples of lower limb strengthening exercises without weight machines are listed below
Lower Limb Strength Exercises
(high weight and low repetition)
|Exercise #1 |
Knee extensions in sitting
|Exercise #2 |
|Exercise #3 |
Climbing stairs or use a stepping box
Tip: It is often advisable to perform lower limb endurance training as a “warm-up” before strength training.
Examples of upper limb strengthening exercises without weight machines are listed below. The program Exercise Professional needs to review the most appropriate exercises based on the patient’s active range of motion (ROM) and consider any past or present shoulder/upper limb musculoskeletal concerns.
Upper Limb Strength Exercises
(high weight and low repetition)
|Shoulder press||The following exercises were adopted from:
Lung Foundation Australia’s Better Living with Exercise- Your Personal Guide
The following exercises were adopted from22:
Ellis, B. P. T. & Ries, A. L., 1991. Upper Extremity Exercise Training in Pulmonary Rehabilitation. Journal of Cardiopulmonary Rehabilitation and Prevention, July, 11(4), pp. 227-231.
These exercises are to be performed whilst seated in a chair with back support.
Sit with your feet flat on the floor, and the small of your back pressed back into the chair.
Your elbows must not be locked.
All arm movements should be performed on exhalation (breathing out).
Each exercise is to be performed 10 times.
Rest for 1 minute. This forms one set. Build up to 3 sets.
When you can perform 3 sets for two weeks, increase your weight by 0.5kg.
Arms crossed in the lap, elbows straight and palms facing down.
Lift arms up, out and apart until they are fully extended above the head with palms
Return to starting position.
Arms down by side, elbows straight, and palms facing backwards.
Lift arms up, out and apart until they are extended above the head with palms facing backwards.
Return to starting position.
Arms down by sides, elbows straight and palms facing backwards.
Arms are lifted up and out to the side (horizontal) while rotating hands to finish with the palms facing forward.
Arms are moved forward to meet in the middle.
Return to starting position.
From22: Ellis, B. P. T. & Ries, A. L., 1991. Upper Extremity Exercise Training in Pulmonary Rehabilitaiton. Journal of Cardiopulmonary Rehabiliation and Prevention, July, 11(4), pp. 227-231.
Strength training with fixed weight machines:
- Leg press.
- Quadriceps extension.
- Lat/chest pull down for latissimus dorsi.
- Chest press for pectorals.
- Upright cable pull for trapezius
The appropriate intensity for strengthening exercises can be prescribed based on:
A. One repetition maximum.
B. Weight repetitions.
A. Prescribing intensity based on one repetition maximum
The maximum weight that can be lifted once by a particular muscle group is known as the one repetition max (1 RM)*. The 1 RM value is used to prescribe the intensity of the strength training program:
Choose an exercise with a weight that can be performed a maximum of10 times with correct technique (ie 10 RM).
- Start with a weight of 60 to 80% of the patient’s 1 RM weight.
- Perform one set (10 repetitions) of a particular exercise.
- Aim to increase the weight up to 80% of the patient’s 1 RM while ensuring that the patient performs the exercise with the correct technique.
- After the patient can perform three sets of an exercise, the weight may be increased.
*Caution: Testing pulmonary rehabilitation patients for their 1 RM may not be advisable. There may be concerns regarding joints, ligaments and bone density in many of these patients.
B. Prescribing intensity based on weight repetitions
To avoid problems with testing patients for their 1 RM, the intensity of exercise may be prescribed in either of the following ways:
- Use a sub-maximal test to estimate the patient’s 1 RM. The patient lifts a weight that they can only lift 2 to 3 times; this weight is taken as 80% of the patient’s 1 RM. From this, the 1 RM can be calculated and the intensity prescribed as for the 1 RM method (see above).
Use a weight that the patient can only lift 6- 10 times.
- Perform one set (10 repetitions) of a particular exercise, then rest.
- Try to limit the rest period between each set of 10 repetitions to less than two minutes.
- Once the patient can perform 3 sets of a particular exercise, the weight can be increased by 5% or between 0.5 kg to 5 kg depending on which muscle group is being trained. For upper body strength training, ask the patient to move their arms up as they breathe in, and down as they breathe out.
- These exercises can be performed in the sitting position, with the back supported.
- These exercises should not cause significant discomfort to the shoulders.
The duration of a strength training session will be the time it takes to complete the appropriate number of sets.
The frequency for strength exercise sessions should be two or three times per week. Patients should ensure they have at least one day of rest between strength training sessions.