The American College
of Sports Medicine (ACSM) suggests considering incorporating
interval training after a period of initial conditioning typically 2-3 months intermittently to avoidexcessive orthopaedic stress (ACSM, 2014). Additionally,
HIIT may require initial supervision in untrained and high
risk individuals (Kessler et al., 2012), and may transiently
increase the risk of cardiac events in people with underlying
undiagnosed CVD (Mittleman et al., 1993).