Supervised Exercise for Post-surgery Colorectal Cancer Patients

The study aims to provide a structured exercise programme to investigate whether a structured exercise programme following discharge from hospital will aid return to full activity. Exercise programmes are a well-tested and effective method of improving fitness in the healthy population. The government guidelines for adults aged 19 and above are to do at least 150 minutes of moderate intensity or 75 minutes of vigorous activity a week which can be split over multiple days. This does not require specialist equipment or costly interventions and include simple measures such as brisk walks and lifting weights. In conjunction with set resistance exercises, the investigators aim to use this as the target to provide a regimen that reaches this target for patients. Physical activity will also be measured at four timepoints during the study using a non-invasive physical activity monitor (ActivPAL) to compare between the intervention and control group.

Recruitment Understandably for the potential recruits this will be a difficult and emotional time period given their significant diagnosis that will have been given very soon prior to the research team's first interaction with them. Participants will be recruited in the outpatient setting but after the diagnosis and treatment plan has been made and conveyed by their parent team. Patients will be given all the information and at least 48 hours to consider their involvement in the study. They will then be re-contacted them via telephone and if they agree, researchers who are trained in taking consent will complete the consent process with the patient. No patients will be included who lack capacity or are in any other way unable to give informed consent. The research group have previously recruited for several prehabilitation studies in this way with good patient feedback and no reports of psychological harm.

Exercise

These guidelines are suitable for older participants with necessary adaptations. However, it is assumed that a small number older of participants may struggle to achieve these targets as they were not achievable for them prior to diagnosis and surgery. The investigators have a long and safe track record of exercise in the elderly in studies performed by the group, and clinical researchers will closely supervise the CPET. Unfamiliarity with exercise in itself is not a reason for non-inclusion in the study, but a more graduated increase in effort may be required for individual participants. There are clear inclusion and exclusion criteria outlined to minimise the risk of adverse outcomes following exercise in the participants. Cardiopulmonary exercise testing (CPET) will be included in the functional assessments at four points during the study. There is a theoretical risk of exercise-induced pathology that may occur secondary to this. The guidelines will be followed for absolute contraindications as laid out by the POETTS consensus guidelines (2018) and ATS/ACCP statement on CPET (2003). These include but are not limited to:

• Acute myocardial infarction (3-5 days)
• Unstable angina
• Uncontrolled arrhythmias causing symptoms or hemodynamic compromise (200 mm Hg systolic, 120 mm Hg diastolic)
• Syncope
• Active endocarditis
• Acute myocarditis or pericarditis
• Symptomatic severe aortic stenosis
• Uncontrolled heart failure
• Acute pulmonary embolus or pulmonary infarction
• Thrombosis of lower extremities
• Suspected dissecting aneurysm
• Uncontrolled asthma
• Pulmonary edema
• Room air desaturation at rest
• Respiratory failure
• Acute non cardiopulmonary disorder that may affect exercise performance or be aggravated by exercise (i.e. infection, renal failure, thyrotoxicosis)
• Mental impairment leading to inability to cooperate These patients will not be included in the study. Also, any abnormal results picked up at screening will warrant exclusion from the study, and the PI will communicate these to the participants' GP.

If any of the following occur both during exercise or CPET testing the programme will be terminated immediately and the participant withdrawn:

• Chest pain suggestive of ischaemia
• Ischemic ECG changes
• Complex ectopy
• Second or third degree heart block
• Fall in systolic pressure 20 mm Hg from the highest value during the test
• Hypertension (250 mm Hg systolic; 120 mm Hg diastolic)
• Severe desaturation: SpO2 ≤ 80% when accompanied by symptoms and signs of severe hypoxemia
• Sudden pallor
• Loss of coordination
• Mental confusion
• Dizziness or faintness
• Signs of respiratory failure CPET testing is the standard test for qualification of lack of cardiorespiratory fitness before operation and is used to stratify risk in higher risk patients as standard of care in the UK.

These guidelines will also be applied to those performing alternative forms of exercise such as brisk walking/running and resistance exercises. The resistance exercise component will via the use of resistance bands and therefore does not require equipment such as weight machines or free weights which can cause injury if applied incorrectly.

Those who volunteer for the study may be more active by virtue of a desire to be included. There is the potential for outcomes not being as generalizable to the whole population regardless of pre-existing physical activity, and also, impact of interventions may be lessened as both groups may be more fit than some groups of those who present for surgery.