Exercise as medicine for heart failure

The current project aims to trial a new form of exercise, utilising eccentric muscular contractions, which have unique characteristics that allows for peripheral (muscular) gains at lower oxygen consumption and promisingly suggests enhanced functional benefits at lower cardiovascular risk. Participants randomised to the intervention group will receive eccentric cycle training. Eccentric training of the lower limb muscles will be performed on an eccentric cycle ergometer that uses a motor to drive a bicycle crank in reverse. The eccentric exercise will be performed over the same duration and at a cardiovascular intensity equivalent to the comparator (concentric cycling) group (up to 70% HRR). Exercise prescription will be undertaken in the Exercise Physiology Laboratory and Cardiac Gymnasia at Fiona Stanley Hospital, under the supervision of an exercise specialist with experience working with advanced HF patients. Our approach is to individually prescribe exercise predicated on baseline assessment. Exercise training is initiated one-on-one, and then continues in closely supervised small groups, to ensure strict adherence to the principles of the study’s exercise intervention. Participants will be continuously monitored with ECG telemetry. Facilities have full resuscitation equipment and rapid response, hospital accredited emergency support should that be required. The intervention is a total of 14 weeks in duration. All sessions will be supervised by an accredited exercise physiologist to ensure participant safety, and robust adherence to exercise prescription. Participants will be continuously monitored with ECG telemetry, and technique, intensity monitored by the investigators. Familiarization: Participants will undertake an initial 2-week familiarization block, of low level eccentric cycling to mitigate the potential of any exercise-induced muscle soreness or damage. Progression: Training will then be progressed over several sessions to a workload corresponding to 50% of heart rate reserve (HRR), determined during baseline aerobic capacity assessment, with further progression up to 70% HRR (as individually tolerated). Training Session format: Each group will undergo warm up and stretching routine for 10mins, followed by a total of 40mins of eccentric cycle training, then a 5min cool down. Training will occur 2 times per week. Borg’s Category Scale will be used to rate perceived exertion between the two modes of training.