Physiological and biomechanical responses from using mini-bikes

The study will require participants to attend a single laboratorial session to complete the following: • the Exercise and Sports Science Australia (ESSA ) pre-exercise screening questionnaire, • Stature and body mass using a stadiometer and a weight scales, respectively, • Cardiorespiratory assessment using a mini-bike and a cycle ergometer, in random order between participants. Mini-bikes (https://www.kogan.com/au/buy/casami-portable-exerciser-mini-bike-trainer-exercise-machine-desk-home-gym-pedal-cycle-7646650302616/?utm_source=Bing&utm_medium=product_listing_ads%7Bifpe%3Aproduct_extension_ads%7D&utm_campaign=Kogan+AU+-+Standard+Shopping+-+Placeholder&utm_term=4574930466662083&utm_content=Ad+group+%231) are small size bikes with shorter cranks enabling cycling when sitting on a sofa or chair. After completing these questionnaires and measurements of stature and body mass, participants will be prepared with a heart rate monitor and 17 wearable sensors attached to their body to monitor body movements when using a mini-bike and a cycle ergometer. These sensors are small and light weight (3x3 cm with ~5g each) and will be attached using velcro straps in their feet, lower legs, upper legs, pelvis, upper arms, forearms, head (using a head band) and torso (using a customised jersey). The sensors communicate wirelessly with the computer. Participants will then warm-up for 10-min on a treadmill. Upon completion of the warm-up (i.e. walking at self-selected intensity on a motorised treadmill), participants will be randomly assigned to the cycle ergometer or the mini-bike (using a random number generator tool). They will be equipped with a mask to enable collection of gas exchanges using a metabolic cart. They will perform 15-min in each mode of exercise at self-selected intensity. Instructions will be provided to ensure that they cycle at an intensity that would enable them to perform other activities such as phone browsing or TV watching. After the first block of 15-min, they will rest for 15-min before transitioning to the other mode of exercise. Direct observation will be used to ensure adherence to the interventions. During both modes of exercise, gas exchange and heart rate will be collected continuously. Rate of perceived exertion (RPE) will be collected every 5-min along with movement using the wearable sensors. The mini-bike and the cycle ergometers will be instrumented to collect pedal forces, which will be later used to determine joint loads.