Title of study: Does the heart fatigue following prolonged mountain endurance exercise?
Collaborating Institutes: This study forms part of ongoing collaborative research between; The University of Wolverhampton, Manchester Metropolitan University, St. Georges Hospital London, and New Cross Hospital Wolverhampton.
Reasoning behind the study: A huge amount of research has been completed looking at the effects of exercise upon the heart. The bulk of these studies have examined both the structure (size) and the function (efficiency) of the heart. Through this research it has been accepted that in an apparently healthy person, exercise (especially endurance exercise) is beneficial to both the heart and general wellbeing. It has been shown that the heart muscle adapts to training in a similar fashion to other muscles. Studies have demonstrated that with training the heart can actually enlarge and become stronger. The adaptation that occurs with endurance training has led to the conception that endurance exercise brings only benefits to the heart, and that perhaps the more endurance exercise completed the better!
Recent research has been in disagreement with the above position, as some studies have suggested that the heart may actually fatigue and experience minor reversible damage during bouts of prolonged endurance exercise (ironman triathlons, ultra-marathons). To date the studies examining this area have been of a conflicting nature. Some demonstrating damage to the heart, whilst others not. This therefore needs to be clarified.
As well as the recent conflicting research there is an increasing participation rate within prolonged endurance events. These factors highlight the need to better understand the effects of endurance exercise upon the body and specifically the heart, so as to limit any potential risks. Therefore, the purpose of the proposed study at the Lowe Alpine Mountain Marathon is to examine how two bouts of endurance exercise on consecutive days affect the heart. The study will hopefully answer some of the questions highlighted below:
· Is the hearts structure and function affected by a single bout of endurance exercise (day 1)?
· Is the hearts structure and function affected by repeated bouts of endurance exercise (day 1&2)?
· Does a single bout of endurance exercise cause the release of heart specific markers into the blood? (day 1)
· Do repeated bouts of endurance exercise cause the release of heart specific markers into the blood? (day 1&2)
· If the hearts structure and function is affected by endurance exercise, how and why is it affected?
Testing sessions: The testing will be carried out prior to the start of day one (possibly at registration), at the mid-way camp, and immediately following race completion (day 2). Both the initial testing and the final day testing will follow the same format. This will comprise of an echocardiograph (echo), an electrocardiograph (ECG) and the taking of a blood sample. Both the echo’s and ECG’s are non-invasive and will cause no discomfort. The blood sample will be similar to that taken during a normal blood test. In total this should take no longer than 20 minutes. The testing session at the mid-way camp will only involve the collection of a blood sample, and therefore should only take 5 minutes.
Schematic of testing:
A Day 1 B Day 2 C
A= INITIAL TESTING (ECHO, ECG, BLOOD SAMPLE)
B= MID-CAMP TESTING (BLOOD SAMPLE)
C= POST RACE TESTING (ECHO, ECG, BLOOD SAMPLE)
Volunteers: It would be beneficial to gain a cross section of competitors (approx.20) from the elite level to the non-elite to take part in the study.
Volunteer commitments: The success of the study is dependent upon the volunteers, and although the time commitment to the volunteer is fairly substantial it will be kept to the essential minimum. Before taking part in the study the volunteer will have to read and sign an informed consent form; this will be made available to the volunteer prior to registration. It is important to stress to potential volunteers that they will have to report to the testing area fairly rapidly following race completion on day 2. Obviously time will be given over for the volunteers to put on some warm clothes and dry off etc. but the testing needs to be completed within 30 minutes of race completion.
Potential benefits: The individual volunteer will gain a greater understanding of the impact of their chosen activity upon them physiologically. The results of the study will lead to a better understanding of how mountain marathons impact the heart. This information will be fed back to the volunteers and race organisers as soon as the results have been collated and written up.
Contact details: Please feel free to contact me at any point with reference to any questions or further information regarding taking part in the study.
address: Rob Shave
The University of Wolverhampton
School of Sport Performing Arts and Leisure