Exercise as therapy for COPD - Is exercise useful for smokers' lungs?
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Chronic obstructive pulmonary disease (COPD) is better known to most people as "smoker's lung". The symptoms remain the same: coughing, increased sputum production and shortness of breath during exertion. If done correctly, exercise can also be a therapeutic alternative to drug treatment for COPD.
Contents
Can you exercise with COPD?
What effect does oxygen supply during exercise have on COPD patients?
Which training is more effective in treating smoker’s lung?
Can lung function improve again in COPD?
Conclusion: No significant benefit from oxygen support
Can you exercise with COPD?
Physical activity and, above all, regular training are among the cornerstones of non-drug therapy for COPD. After just a few weeks, performance improves, which is noticeable both in everyday life and in leisure activities with family and friends. This also increases the quality of life. Both of these have been clearly demonstrated in numerous studies. However, the question of how the best results can be achieved has not yet been clearly answered. There are three areas to consider:
- Do people who do not require oxygen benefit from oxygen supply during exercise?
- Is training with a constant intensity or interval training more beneficial?
- How much can physical performance be improved ?
Other important topics are
- the different effects of training with large and small muscle groups and
- the comparison between strength and endurance training.
The oxygen supply during training is intended to enrich the blood flowing from the lungs to the muscles with more oxygen and thus increase the supply to the muscles. This is intended to increase the possible training load for people with smoker's lungs. This can also increase the training effects .
What effect does oxygen supply during exercise have on COPD patients?
Although an earlier study showed a benefit of oxygen supplementation during exercise for people with smoker's lungs compared to a control group with the same disease who breathed normal air, these results could not be confirmed in later studies.
Recent study results on the treatment of COPD through exercise
The study
A study was recently completed in which COPD patients trained on a bicycle ergometer three times a week for half an hour , initially at 70% of their current capacity, then the load was increased by 5% every three weeks. Half of the subjects were given 4 liters of oxygen per minute via nasal cannulas, the others were given room air at the same current strength. The patients themselves did not know which group they belonged to.
The result
Both groups benefited from the training to a comparable extent: after just twelve weeks , maximum performance had increased - on the bike by 20% and the distance covered in the 6-minute walk test by 12%. Quality of life, which was recorded using a questionnaire, also improved significantly. Even at the end of the study after a total of 24 weeks, there was no difference between oxygen and air supply.
Classification of the results
This was unexpected for us, as a smaller preliminary study had shown that an increased oxygen concentration in the inhaled air had a positive effect on improving performance. There was also a comparison group that received ambient air.
The difference between the two studies is primarily that the COPD patients in the preliminary study breathed through face masks, through which one group was constantly supplied with twice the amount of oxygen as air. When supplied via nasal cannulas, the amount of additional oxygen that can take effect in the lungs depends, among other things, on the ratio of mouth to nose breathing . And when exerting themselves more, everyone tends to breathe more through their mouth, which reduces the amount of additional oxygen taken into the lungs.
Which training is more effective in treating smoker’s lung?
Endurance training can basically be divided into two different forms of exercise: constant performance exercise , where the intensity remains the same during a single unit, and interval training , where phases with high and low intensity alternate regularly. For a long time, only the first form was used in patients.
The study situation – constant exercise intensity vs. interval training in COPD
In 1991, Casaburi's research team showed that intensive training is superior to less intensive training . For the first time, it was demonstrated that physiological parameters in both people with healthy lungs and people with smoker's lungs adapt positively to regular activity . In particular, the ability of the muscles to provide the energy needed for muscle contraction with the help of oxygen and the nutrients carbohydrates or fats is increased.
To answer the question of whether such adaptations are more pronounced with interval training or with constant performance , patients who trained according to the principles described were divided into two groups. To ensure comparability, the total work performed was kept the same.
A more recent study – a 24-week comparison
We investigated the same question intra-individually for 24 weeks. As in the other studies , two groups initially trained at a constant level and at intervals . The constant training group trained for 30 minutes at 70% of maximum performance, which was determined in a gradually increasing test. The other group alternated between 4 minutes of training at 60% and one minute at 110% of maximum performance during the same time. The load was increased by 5% every three weeks.
An interim test was completed halfway through the study period. After that, the groups changed training forms. In line with the results of other studies, we found no significant difference between the adaptations to the two training forms. In addition, we asked the subjects about their preferred type of exercise . Around 30% of the patients preferred the constant form and 40% the interval form, while the remaining 30% were indifferent.
These results are very positive for the practical implementation of training measures. It therefore makes no sense to give greater weight to a certain type of exercise and each person can choose their preferred type of training or switch between the two to avoid monotony.
We also found something surprising in this study: Although the intensity was adjusted to the current results after the interim test and performance was increased progressively as in the first 12 weeks, there was no further increase in physical fitness up to week 24. Of course, such results can only be interpreted in relation to the conditions that actually existed.
Can lung function improve again in COPD?
It therefore appears that with endurance training on a bicycle lasting 30 minutes and carried out three times a week, the limit of training adaptation is already reached within 12 weeks, even with increasing intensity. This could be attributed to the fact that lung function is hardly improved by training the leg muscles and this becomes a limiting factor at a certain performance level.
The next steps should be to investigate whether strength training – isolated or in combination with endurance training – allows for greater gains and whether endurance training with smaller muscle groups , which is less limited by lung function, allows for a greater increase in performance.
Conclusion: No significant benefit from oxygen support
In summary, it can be said that for training therapy through endurance training, oxygen support does not provide any significant benefit for patients who do not require oxygen and that interval training is equivalent to constant training . In both forms, the intensity of the exercise must be sufficiently high to achieve significant improvements in physical performance. The correct intensity can easily be determined by a specialist using bicycle ergometry.
