Assessing the Impact of Age, and a Short-term High-intensity Interval Training (HIIT) on Skeletal Muscle Mass and Mitochondrial Activity

"Each HIIT session last 15 minutes. Participants will be asked to measure their own heart rate during their rest periods and provided with an estimated max heart rate which they should be aiming to achieve within the final 2 exercises. Participants will be provided with a logbook to record the heart rate achieved in each exercise. The regimen will include:~* 2 min warm-up: jogging on the spot~* Each of the following exercises performed for 60seconds, interspaced by 90 seconds rest~ * Star jumps~ * Standing squats~ * On-the-spot sprints~ * Standing squats~ * Star jumps~* 2 min cool-down: jogging on the spot"

"Each RET session lasts an estimated 20minutes. Participants will be provided with a set of resistance bands to provide resistance to their workout, and a logbook to record the number of repetitions and band used.~Each session will include:~* 2 min warm-up jogging on the spot~* 2 sets of 12-15 repetitions of:~* Squats~* Hip flexion~* Hip extension~* Hip abduction~* Seated row~* Bench press~* Lateral raises~* 2 min jogging on the spot cooldown.~Each exercise will be separated by 1-minute rest, with participants encouraged to workout to mild fatigue on their final repetition in each set. If able to perform more than the allocated maximum of 15 repetitions prior to fatigue, then participants will be informed to increase the resistance by using a tougher resistance band."