Exercise as it relates to Disease/The effectiveness of high-intensity training following lung cancer surgery

This is a critique of the article "High-intensity training following lung cancer surgery: a randomised controlled trial" By Elisabeth Edvardsen, Ole Hanning Sjkonsberg, Ingar Morton Holme, Lars Nordsletten, Finn Borchsenius, Sigmund A Andersen (2014).

What is the background to this research?
Lung cancer significantly affects the cardiorespiratory fitness of the sufferers. Lung cancer accommodates 15% of cancer and 80% of lung cancers are Non-small Cell Lung Cancer. Sleeve resection surgery is required in Non-small Cell Lung Cancer that are in the large airways of the lungs. It involves cutting across the airway below and above the tumour, then extracting it. After the resection surgery peak oxygen uptake decreased by 20% from before the surgery. Exercise is extremely important in reducing all-cause mortality by 30-50%. Low peak oxygen uptake prevents a higher risk for mortality when patients have had a lung resection.

This paper looks at the effects of high-intensity training on people, 5-7 weeks after lung cancer surgery. This article provides insight into the positive outcomes of high-intensity training on non-small-cell lung cancer sufferers instead of aerobic and endurance training that is more commonly studied. Only one other study before this study had looked at the peak oxygen uptake after significant lung surgery and it was an uncontrolled study. This research is extremely important as it is very important to look at how the quality of life can be improved for people living with lung cancer.

Where is this research from?
This article was conducted in Oslo Norway in the Oslo University Hospital, pulmonary department. This department is still studying lung cancer with their most current study looking at the consensus for lung cancer transplants. The university has a ranking of 119 for 2022.

The authors have not published any other article together. Elisabeth Edvardsen is the lead author and a postdoctoral fellow specialising in Cardiopulmonary exercise testing, Cardiorespiratory fitness, and Cancer. Elisabeth Edvardsen has studied cardiorespiratory fitness in men with lung cancer with relation to incidence and mortality, which is similar to this study. Elizabeth Edvardsen has been cited 747 times from her publications showing good credibility and a valuable source for other research. This article is from the journal Thorax, which is an official journal of the British Thoracic Society. Thorax is one of the worlds leading journals for respiratory medicine. There is no belief to be bias in the British Thoracic Society because it is a well-governed organisation that wants to provide credible sources. Also, there are believed to be no conflicts of interest from previous studies and authors.

What kind of research is this?
This study was a single-blind randomised control trial of strength and high-intensity training. The single-blind randomised means that the participants did not know what group they were in. This method is effective in reducing participant bias.

Other research studies had similarities to the ones assessed in this study. A 6-minute walk test was used in another study and it was found to have shown significant improvements after the intervention. It also reported less breathlessness and a higher quality of life.

What did the research involve?
An external statistician placed the participants randomly into either the exercise or control group. This reduces the risk of selection bias. 30 were assigned to the exercise intervention and 31 to the control group. 25 of the participants in the exercise group completed the intervention. The exercise group trained for 20 weeks, 3 times a week, for 60 minutes. The control group participated in normal postoperative care. The sessions started with a cardio warm-up. The rest of the session incorporates interval training, inspiratory muscle training, and resistance training. The tests are done before and after the intervention include:

Limitations
 * Peak oxygen uptake was assessed through graded exercise on a treadmill
 * Maximum leg strength was the maximum strength lifted by the hip and knee joints in 1 repetition
 * Hand strength was assessed by grip strength dynamometer
 * DEXA was used to measure total muscle mass
 * To evaluate the quality of life the participants completed a 36-question survey

Participant recruitment was only newly diagnosed patients with NCLC. The intervention may not be applicable for people who have had lung cancer for longer periods of time or people who have had a relapse of cancer. Another limitation is that the participants had to speak Norwegian to be a part of the intervention. The results could differ if applied to people of different nationalities. The sample size is small with only 61 people participating in the study. Larger sample size can give the study more credibility and be able to show more differences in results. A limitation of the methodology of the RCT is that experimenter bias can occur. The experimenter can alter the results of the study to look more credible.

What were the basic results?
Peak Oxygen Uptake- exercise group improved significantly, control only slightly improved

1RM in leg press- exercise group improved significantly, control slightly decreased

Hand Grip Maximum- exercise group improved significantly, control slightly improved

Total muscle mass- exercise group improved slightly, control similar to before intervention

Quality of life Physical component- Exercise group improved significantly, control group decreased significantly

The adherence to the exercise intervention in the exercise group was 88±29%. The participants stated that they enjoyed the program and the intensity was well tolerated. Only one injury was reported which the researchers stated was a fractured hip in balance training. The results discussed Muscle mass, QoL, adherence to training, and strength tests were discussed appropriately. Peak oxygen uptake was reinforced many times but it's suitable it was the primary outcome of the research.

What conclusions can we take from this research?
The study showed statistically significant improvements in daily physical functioning, quality of life, muscle mass, and peak oxygen uptake. This research proves that without exercise the quality of life will significantly drop and the peak oxygen uptake only slightly improves. The adherence from the intervention were high so questions can be asked if the difficulty of the exercise could've been increased. Further research for this study should include a follow-up with the patients 6 months after the intervention to see if they are continuing with the exercise.

This study aligns with another RCT in 2014 that looked at the effects of exercise training for people following lung resection for non-small cell lung cancer. It shows similar results to this study with finding statistical significance in quality of life and forced expiratory rate.

Practical Advice
The participants need to be supervised by exercise physiologists or qualified health professionals. It is recommended to check on HR, BP, and other critical measures while exercising to ensure the participant is not over-exerting and putting them-self at risk. For further research comparing high-intensity training to different exercises to see the most effective exercise type, to improve quality of life for lung resection patients. For the exercise 80-95%, MHR is recommended to see the most adaptations. Recommended exercise to start is walking up a hill or on a treadmill. After lung resection surgery all doctors should strongly encourage exercise to help with their recovery.



Further information/ resources
Concerned about lung cancer:


 * https://www.cancer.org.au/cancer-information/types-of-cancer/lung-cancer

Benefits of exercise for lung cancer sufferers:


 * https://www1.racgp.org.au/ajgp/2020/april/physical-activity-for-people-with-lung-cancer
 * https://www.lung.org/lung-health-diseases/lung-disease-lookup/lung-cancer/treatment/stay-healthy/physicial-activity-and-lung-cancer