Exercise as it relates to Disease/The feasibility of high-intensity interval training and moderate-intensity continuous training on Crohn’s Disease patients

This Wikibooks page is a critical appraisal of the research article "High-intensity interval training and moderate-intensity continuous training in adults with Crohn's disease: A pilot randomised controlled trial" by Tew. G.A. et.al (2019). From the BMC Gastroenterology.

What is the Background to this Research?
Crohn’s disease (CD) is an inflammatory bowel disease that impacts the patient’s immune system from functioning effectively, and produces an inflammatory response in the digestive tract walls, causing symptoms such as abdominal pain and diarrhoea. CD patients also suffer from bone mineral loss and therefore are included into the moderate to high risk factor for individuals exercising. Exercise is recommended as it can help patient’s cope with symptomatic issues such as fatigue, inflammation, and mental health, whilst lowering their Crohn's Disease Activity Index (CDAI).

There are controversies surrounding the topic of exercise involving Crohn’s disease patients as they provide a moderate to high risk. It was outlined as too high of a level of intensity of exercise may cause heartburn and diarrhoea and other acute gastrointestinal bleeding issues, and is particularly prevalent in endurance runners.

This paper entails the feasibility of two exercise modules test Crohn’s disease patients exercising at a high-intensity interval training (HIIT) level and at a moderately-intense continuous training (MICT) level. Relating to current research, it investigates how intense and how much exercise a Crohn’s disease patient can do without exacerbating their symptoms. This research provides insight and a reliable foundation for future expansions of research into exercise with Crohn’s disease patients, as current research predominantly reflects low-intensity exercise.

Where is the Research From?
This research article was published by the reputable journal publisher, BMC Gastroenterology. Although, it is a reasonably new source, this journal is highly accepted as a reputable peer-reviewed source and covers technology, gastroenterology, and the medicines categories.

Recruitment was taken from 3 private hospitals in England. The exercise modules were conducted at the University of Winchester by Garry.A. Tew. The data was analysed at the University of New York, York’s Trials Unit. The paper was funded by the Living with IBD Research Programme at Crohn’s and Colitis UK, and research continued for as long as they were funded for. It was noted that the source of funding had no influence on the outcome and analysis of the results.

The authors have a distinguished background. Specifically, Professor Garry.A Tew who has 86 research papers, investigating the effects of exercise-based programs on specific communities or health diseases. Professor Tew’s fellow co-authors; Dr Leighton, Dr Bottoms, Dr Carpenter, Dr Anderson have done 3 other papers which embark on further research into Crohn’s disease and the effectiveness and quality of life from exercising with CD.

What Kind of Research Was This?
This research article is stated as a three-arm pilot randomised trial. Participants were randomly assigned to the High-intensity interval group, moderate-intensity continuous group, and parallel, a usual-care as the continuous group to standardise results collected. A pilot study is the necessary preliminary trial to then further expand upon to a randomised controlled trial which is the gold standard of studies. Due to the delivery of the programs, it would be evident to the participants which intervention they were in. Other pilot trial investigations found correlations of lean mass generation with high and moderate exercise, correlations of higher quality of life , and without exacerbating any symptoms and placing their CDAI in a critical state. .

The authors disclosed that there were no conflicts of interests.

What Did the Research Involve?
The trial consisted of 53 participants clinically diagnosed with Crohn's disease and were randomised into 3 separate programs via a statistician from the Yorks Trials Unit. Participants were to complete 28 or 38 minute sessions 3 times a week over the course of 12 weeks. All exercise trials took place on a cycle ergometer. The high intensity and moderate intensity programs both started off with a 5-minute warm up at 15% peak power output (PPO) (determined via baseline cardiopulmonary testing), with a 3-minute cool down session also at 15% PPO. Heart rate and peak oxygen uptake (POU) was recorded throughout the trial to identify PPO. The methodology could have been reduced to a 2-arm study, to limit difficulty of recruiting participants.

There were several limitations to this research paper:


 * Sample size was limited
 * Physical activity was self-reported
 * Endoscopies weren’t used to evaluate the degree of inflammation in the gastrointestinal tract
 * No blinded allocation for follow up procedures

What Were the Basic Results?
The HIIT in comparison to the MICT have both provided insight to being beneficial for Crohn’s disease patients to partake in both activities. Peak oxygen uptake was significantly improved in the HIIT program (2.4 mL/kg/min increase) in contrast to the MICT program (0.7mL/kg/min increase) when tested for the baseline to 3 retest protocol. Maximum heart was 92% for HIIT and 68% for MICT. The CDAI score decreased for HIIT participants and increased slightly for the MICT, however both scores are still considered as asymptomatic remission. Majority of patients reported that their intervention improved the quality of their life without causing CD symptoms and inflammation. There were also statements made how the trial motivated them to continue with the regime. There were a couple of adverse-events that were due to the exercise interventions. It was reported that their CDAI scores were increased in disease activity, which returned back to the baseline measure within 1 week.

What Conclusions Can We Take From This Research?
The High-intensity interval and moderate-intensity continuous training programs have been found to be correlated with improving patients quality of life, peak oxygen uptake, and lowering their CDAI score. Participants were able to maintain their results with the 3-month follow up procedure. This study also provided strong statistical evidence for the HIIT group providing better results than the MICT group as they were able to increase their peak oxygen uptake whilst decreasing they CDAI score. The control group didn't provide much information other than context for the study, therefore using a 2-arm study would be beneficial for future studies. There unfortunately were adverse effects during the trial, however information was provided that it was a combination of the participants medications and the program that potentially caused issues, therefore, the consideration of how safe this program is should be researched further in larger sample-sized settings.

Practical Advice
For future research, investigating patients that have no previous and current history of private institute benefits as healthcare is not accessible to all and therefore, a different will not be provided with the same level of care as patients in private hospitals. Adverse effects of exercise should be expanded upon in research as exercise can affect individuals on specific medications or stages of CD. It would be beneficial if a randomised controlled trial further expanded upon the safety of higher intensities of exercise on CD patients as several participants were interested in doing variations of high-intensity exercises. Strength training has been correlated with providing a feasible and safe option for management of symptoms within CD patients.

Further Information/Resources
For further information on management of Crohn's disease using physical activity please read the following:


 * 1) Progressive resistance training improves muscle strength in women with inflammatory bowel disease and quadriceps weakness
 * 2) P026 Relations between physical activity, diet, and body composition in paediatric patients with inflammatory bowel disease
 * 3) Moderate endurance and muscle training is beneficial and safe in patients with quiescent or mildly active Crohn’s disease
 * 4) Randomised clinical trial: combined impact and resistance training in adults with stable Crohn’s disease.