Aerobic exercise, which includes activities such as running and walking, conditions the cardiovascular system and builds endurance. Distance running is a popular form of aerobic exercise and a competitive sport where overuse injuries are often a result of training (Wiegand et al., 2019). When runners are injured, they may need to reduce or sometimes stop their training for several weeks to months (Liem et al., 2013). Within only three weeks of stopping training, endurance-trained athletes experience a significant seven percent decrease in maximal oxygen consumption, or the amount of oxygen they take in during maximum effort aerobic exercise. This decrease in oxygen consumption is an indicator of decreased fitness level (Coyle et al., 1984; Neufer, 1989).
When recovering from injury, runners may engage in rehabilitation programs to mitigate losses in their aerobic fitness, or detraining (Fredericson et al., 2006). Blood flow restricted (BFR) exercise is a rehabilitative modality that allows individuals to gain fitness benefits while working under lower mechanical loads and intensities (Hughes et al., 2019). As an exercise science major with a love of sports medicine, and as a chronically injured distance runner on the University of New Hampshire’s women’s cross country and track teams, I sought to combine my personal and academic interests by conducting research on this topic for my Honors thesis. With funding from a Summer Undergraduate Research Fellowship (SURF) from the Hamel Center for Undergraduate Research, my objective was to study cardiorespiratory and metabolic responses to low-intensity blood flow restricted running.