Table 1.

Description of feasibility domains assessed in the current study

Domain	Description	Student outcomes	Teacher outcomes
Acceptability	The extent to which the program is considered suitable, satisfying, or attractive to program participants	• Program satisfaction • Barriers and motivation to HIIT • HIIT sustainability • Group exercise preferences	• Program satisfaction • Intervention sustainability
Implementation	The extent, likelihood, and manner in which the program can be fully implemented as planned	• Session adherence • Session intensity	• Sessions delivered • Session duration • Quality of session delivery
Adaptation	The extent to which an existing program can be adapted to fit the needs of different populations	n/a	• Qualitative description of session adaptations • Adaptation to school characteristics
Practicality	The extent to which the program can be delivered using existing resources or with limited resources, and without outside intervention	• Practicality of program resources	• Ease of implementation • Session timing acceptability • Adverse events
Preliminary efficacy	The extent to which the program works in making positive changes to muscular fitness and functional performance	• Sit-to-stand test • Push-up test • 6-min run/walk test • Mood state	n/a