None listed
Conditions
Brief summary
Mitochondria are compartments within our cells that facilitate various important processes, including that of energy generation. Mitochondria rapidly adapt to changing needs within the cell through a process called mitochondrial biogenesis, by which, new components are added to the network of mitochondria. Mitochondrial biogenesis is stimulated in skeletal muscle by exercise, however, the signalling that allows this to occur is poorly understood. This project aims to uncover the different signalling pathways activated by exercise in skeletal muscle using novel techniques combined with advanced statistical analysis. Analysis will be performed on quadriceps muscle biopsies collected from forty untrained men and women (equal numbers of each). Using samples both prior, in the middle, and at multiple time points after exercise, we will capture all changes in gene expression and protein localisation. This data will be combined with measurements of participants' fitness before and after training to generate a timeline and predictive model of mitochondrial biognesis signalling. Expanding the knowledge of mitochondrial biology will have many ramifications for both athletic and biomedical disciplines. Recently, links between the function of mitochondria and life expectancy have been discovered, with numerous diseases characterised by mitochondrial dysfunction, such as diabetes, cardiomyopathy and various neurological disorders on the rise globally. We hope by understanding how exercise triggers mitochondrial biogenesis, exercise can be used to a greater effect as therapy for these diseases. By applying this methodology to different exercise intensities and durations, better exercise prescription for athletes can also be determined. Additionally, the identification of novel mitochondrial biogenesis regulators may enable new targeted drugs that aid treatment of mitochondrial dysfunction or mimic exercise in those who cannot do exercise.
Interventions
High-intensity interval training (HIIT) exercise.
Participants will train 4 times per week throughout the 8-week period. Each exercise session will consist of four 4-minute intervals at an intensity of 80% of a participants peak power output on a stationary bike. Each interval will be seperated by 2-minutes of rest for a total session time of 22 minutes. Each training session will be performed at the Exercise Physiology laboratory at Footscray Park Campus (Victoria University) one-on-one with a
High-intensity interval training (HIIT) exercise. Participants will train 4 times per week throughout the 8-week period. Each exercise session will consist of four 4-minute intervals at an intensity of 80% of a participants peak power output on a stationary bike. Each interval will be seperated by 2-minutes of rest for a total session time of 22 minutes. Each training session will be performed at the Exercise Physiology laboratory at Footscray Park Campus (Victoria University) one-on-one with a researcher to ensure compliance. This intensity has been selected as it has previously been shown to elicit a large response within muscle to generate mitochondrial biogenesis. Muscle biopsies and blood samples will be collected from participants by an experienced medical doctor during the first HIIT session (at timepoints before, in the middle of, and at timepoints 0, 3, 6, 9, 12, 24, and 48 hours after exercise completion) at the beginning of training and after the completion of the 8-weeks of training.
Sponsors
Victoria University
Study design
Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
- Aged 18-40 years old, Men & Women - Be generally ‘healthy’: Non-smoker, free from pre-existing medical conditions (e.g., heart rhythm disturbance, elevated blood pressure, diabetes), cardiovascular abnormalities, respiratory conditions and musculoskeletal injuries. - Not taking prescription medication (e.g., beta-blockers, anti-arrhythmic drugs, statins or insulin sensitising drugs). - Undertaken less than the current weekly physical activity guidelines for adults (150 minutes of moderate intensity physical activity, or 75 minutes of vigorous intensity physical activity) for at least 3 months prior to the study. - Have a body mass index (BMI) between 18.5-34.9 kg/m2
Exclusion criteria
- Current muscle or ligament injury of the lower body. - Current or previous cardiovascular or respiratory condition or abnormality. - Current metabolic disease (e.g. diabetes)
Outcome results
None listed