This project will seek to investigate the effects of exercise intensity, using school-based exercise protocols, on markers of cardiometabolic health in adolescents (aged 11-13 y). This will be achieved by a series of studies, culminating in the design and implementation of an optimised school-based physical activity intervention.
The project will begin by creating and validating a field-based exercise step test against a laboratory-based equivalent. To enhance ecological validity of our work and the real-world applicability of the test, an incremental running protocol will be developed and validated against a gold standard laboratory equivalent. This would allow for the demarcation of exercise intensity domains in a school-setting, leading to the ability to better control exercise intensity in school-based physical activity interventions.
Subsequently, the project will examine the acute physiological & health-related responses to different intensities of exercise in a real-world school-setting. The exercise intensity will be prescribed and fixed, using the method established in first study. This will provide a novel method to compare acute bouts of physical activity. A comparison will be made between exercise in the moderate (typically ~70% HRmax) and heavy (>80% HRmax) intensity domains. The primary health-related outcomes of interest will be markers of cardiometabolic health (namely the inflammatory responses and the glycaemic and insulinaemic response to a standardised meal). Alongside this, qualitative data will be collected through focus groups to understand the perceptions of the young people taking part in the study, which will be imperative for intervention design (see below).
The PhD will culminate with the design and implementation of a school-based physical activity intervention (10 weeks), based on the findings of earlier studies in the PhD. The intervention will examine the chronic effects of interventions performed in different exercise intensity domains (moderate vs. heavy, as previously described), using school-based exercise (and thus having ecological validity). The variables of interest will be risk factors for cardiometabolic disease and heart rate variability.