Table 1.

Characteristics of the included studies.

Study	Population	Groups	Interventions	Exercise Intervention Protocols				Outcomes
				Session Duration (min)	IT Work/Rest Ratio	Frequency	Total Training Time (min)
Healthy participants
Ballesta-Garcia, 2019 [11]	Healthy adults	WB-HIIT vs. WB-MIIT vs. CTL	WB-HIIT: Whole-body exercises at high RPEs WB-MIIT: Whole-body exercises at moderate RPE CTL: No exercise	WB-HIIT: 18–40 WB-MIIT: 18–50	WB-HIIT: 60–90″/120–150″	WB-HIIT: 16 wks, 2×/wk WB-MIIT: 16 wks, 2×/wk	WB-HIIT: 928 WB-MIIT: 1088	MSF
Ballesta-Garcia, 2020 [12]	Healthy adults	WB-HIIT vs. WB-MIIT vs. CTL	WB-HIIT: Whole-body exercises at high RPEs WB-MIIT: Whole-body exercises at moderate RPE CTL: No exercise	WB-HIIT: 18–40 WB-MIIT: 18–50	WB-HIIT: 60–90″/120–150″	WB-HIIT: 16 wks, 2×/wk WB-MIIT: 16 wks, 2×/wk	WB-HIIT: 928 WB-MIIT: 1088	CRF
Blackwell et al., 2017 [20]	Healthy adults	WB-HIIT vs. HIIT	WB-HIIT: Whole-body exercises HIIT: Cycling at 95–110% Wmax	WB-HIIT: 11 HIIT: 11	WB-HIIT: 60″/90″ HIIT: 60″/90″	WB-HIIT: 4 wks, 3×/wk HIIT: 4 wks, 3×/w	WB-HIIT: 132 HIIT: 132	CRF, Metabolic risk factors
* Connolly et al., 2020 [18]	Healthy adults	WB-HIIT vs. CTL	WB-HIIT: Whole-body exercises CTL: No exercise	WB-HIIT: 15	WB-HIIT: 30″ low/20″ moderate/10″ high intensity	WB-HIIT: 12 wks, 3×/wk	WB-HIIT: 540	Metabolic risk factors
Engel et al., 2019 [22]	Healthy adults	WB-HIIT vs. CTL	WB-HIIT: Whole-body exercises with suspension trainer CTL: No exercise	WB-HIIT: 30	WB-HIIT: 20″/10″	WB-HIIT: 8 wks, 2×/wk	WB-HIIT: 480	MSF, Metabolic risk factors
Evangelista et al., 2019 [23]	Healthy adults	WB-HIIT vs. VICT	WB-HIIT: Whole-body exercises VICT: Running at 80% HRmax	WB-HIIT: 20 VICT: 20	WB-HIIT: 30″/30″	WB-HIIT: 6 wks, 3×/wk VICT: 6 wks, 3×/wk	WB-HIIT: 360 VICT: 360	Fat mass, Fat-free mass, MSF
Evangelista et al., 2021 [24]	Healthy adults	WB-HIIT vs. CTL	WB-HIIT: Whole-body exercises	WB-HIIT: 21	WB-HIIT: 40″/20″	Wb-HIIT: 6 wks, 3×/wk	WB-HIIT: 378	CRF, MSF
Islam et al., 2019 [25]	Healthy adults	WB-HIIT vs. VICT vs. CTL	WB-HIIT: Whole-body exercises VICT: Running at 85% HRmax CTL: No exercise	WB-HIIT: 4 VICT: 30	WB-HIIT: 20″/10″	WB-HIIT: 4 wks, 4×/wk VICT: 4 wks, 4×/wk	WB-HIIT: 60 VICT: 480	CRF, MSF
Jimenez-Garcia et al., 2019 [21]	Healthy adults	WB-HIIT vs. WB-MIIT vs. CTL	WB-HIIT: Squats using TRX® at 90–95% HRmax WB-MIIT: Squats using TRX® at 50–70% HRmax CTL: No exercise	WB-HIIT: 25 WB-MIIT: 25	WB-HIIT: 4′/3′ WB-MIIT: 4′/3′	WB-HIIT: 12 wks, 2×/wk WB-MIIT: 12 wks, 2×/wk	WB-HIIT: 600 WB-MIIT: 600	Fat mass, Fat-free mass, MSF
Lu et al., 2021 [26]	Healthy adults	WB-HIIT vs. HIIT	WB-HIIT: Whole-body exercises HIIT: Running	WB-HIIT: 4 HIIT: 4	WB-HIIT: 20″/10″ HIIT:30″/30″	WB-HIIT: 12 wks, 3×/wk HIIT: 12 wks, 3×/wk	WB-HIIT: 144 HIIT: 144	CRF, Fat mass, Fat-free mass, MSF
* McRae et al., 2012 [16]	Healthy adults	WB-HIIT vs. VICT vs. CTL	WB-HIIT: Whole-body exercises CT: Running at 85% HRmax CTL: No exercise	WB-HIIT: 4 VICT: 30	WB-HIIT: 20″/10″	WB-HIIT: 4 wks, 4×/wk CT: 4 wks, 4×/wk	WB-HIIT: 48 CT: 480	CRF, MSF
Menz et al., 2019 [27]	Healthy adults	WB-HIIT vs. HIIT	WB-HIIT: Whole-body exercises HIIT: Running	WB-HIIT: 12–16 HIIT: 12–16	WB-HIIT: 20″/10″ HIIT: 20″/10″	WB-HIIT: 4 wks, 3–4×/wk HIIT: 4 wks, 3–4×/wk	WB-HIIT: 191 HIIT: 191	CRF, Fat mass, Fat-free mass, MSF
Micielska et al., 2019 [28]	Healthy adults	WB-HIIT vs. CTL	WB-HIIT: Whole-body exercises CTL: Whole-body exercises	WB-HIIT: 25	WB-HIIT: 30″/10″	WB-HIIT: 5 wks, 3×/wk CTL: 2 sessions	WB-HIIT: 325 CTL: 50	CRF, Fat mass, Fat-free mass
Murawska-Cialowicz et al., 2020 [29]	Healthy adults	WB-HIIT vs. CTL	WB-HIIT: Whole-body exercises CTL: No exercise	WB-HIIT: 40	WB-HIIT: 20″/10″	WB-HIIT: 8 wks, 2×/wk	WB-HIIT: 640	CRF, Fat mass, Fat-free mass
Schaun et al., 2018 [13]	Healthy adults	WB-HIIT vs. HIIT vs. VICT	WB-HIIT: Whole-body exercises HIIT: Running at 130% VO2 max VICT: Running at 90–95% VT2	WB-HIIT: 8 HIIT: 8 VICT: 30	WB-HIIT: 20″/10″ HIIT: 20″/10″	WB-HIIT: 16 wks, 3×/wk HIIT: 16 wks, 3×/wk VICT: 16 wks, 3×/wk	WB-HIIT: 384 HIIT: 384 VICT: 1440	CRF, Fat mass
Schaun et al., 2019 [14]	Healthy adults	WB-HIIT vs. HIIT vs. VICT	WB-HIIT: Whole-body exercises HIIT: Running at 130% VO2 max) VICT: Running at 90–95% VT2	WB-HIIT: 8 HIIT: 8 VICT: 30	WB-HIIT: 20″/10″ HIIT: 20″/10″	WB-HIIT: 16 wks, 3×/wk HIIT: 16 wks, 3×/wk VICT: 16 wks, 3×/wk	WB-HIIT: 384 HIIT: 384 VICT: 1440	MSF
Schmidt et al., 2016 [30]	Healthy adults	WB-HIIT vs. CTL	WB-HIIT: Whole-body exercises CTL: No exercise	WB-HIIT 7: 1 × 7 WB-HIIT 14: 1 × 7 (wk 1–4), 2 × 7 (wk 5–8)	WB-HIIT: 30″/10″	WB-HIIT 7: 8 wks, 3×/wk WB-HIIT 14: 8 wks, 3×/wk	WB-HIIT 7: 168 WB-HIIT 14: 252	CRF, Fat mass, MSF
Sperlich et al., 2018 [31]	Healthy adults	WB-HIIT LV vs. WB-HIIT HV vs. CTL	WB-HIIT LV: Whole-body exercises (1×/day) WB-HIIT HV: Whole-body exercises (2×/day) CTL: No exercise	WB-HIIT LV: 1 × 6 WB-HIIT HV: 2 × 6	WB-HIIT LV: Not specified (6 min circuit) WB-HIIT HV: Not specified (6 min circuit)	WB-HIIT LV: 4 wks, 7×/wk WB-HIIT HV: 4 wks, 14×/wk	WB-HIIT LV: 168 WB-HIIT HV: 336	CRF, Fat mass, Fat-free mass, MSF
* Wilke et al., 2019 [17]	Healthy adults	WB-HIIT vs. MICT	WB-HIIT: Whole-body exercises MICT: Walking at 50–60% HRR	WB-HIIT: 30 MICT: 50	WB-HIIT: 20″/10″	WB-HIIT: 6 wks, 3×/wk MICT: 6 wks, 3×/wk	WB-HIIT: 540 MICT: 900	CRF, MSF
Specific populations
Batrakoulis et al., 2018 [32]	Obese women	WB-HIIT vs. CTL	WB-HIIT: Whole-body exercises CTL: No exercise	WB-HIIT: 23–41	WB-HIIT: 20″/40″	WB-HIIT: 20 wks, 3×/wk	WB-HIIT: 1761	CRF, Fat mass, Fat-free mass, MSF
Jung et al., 2019 [33]	Women with sarcopenia	WB-HIIT vs. CTL	WB-HIIT: Whole-body exercises CTL: No exercise	WB-HIIT: 25–55	WB-HIIT: 10″/5″	WB-HIIT: 12 wks, 3×/wk	WB-HIIT: 1440	Fat mass, Fat-free mass
Scott et al., 2019 [34]	Obese adults	WB-HIIT vs. HIIT vs. MICT	WB-HIIT: Whole-body exercises at >80% theorical HRmax HIIT: Cycling at 100% Wmax MICT: Running/Cycling at 65% Theorical HRmax	WB-HIIT: 8–16 HIIT: 8–16 MICT: 30–50	WB-HIIT: 60″/60″ HIIT: 60″/60″	WB-HIIT: 12 wks, 3×/wk HIIT: 12 wks, 3×/wk MICT: 12 wks, 3×/wk	WB-HIIT: 432 HIIT: 432 MICT: 1440	CRF, Fat mass, Fat-free mass, Metabolic risk factors

CRF, cardiorespiratory fitness; CTL, control; HIIT, high-intensity interval training; HR, heart rate; HRR, heart rate reserve; HV, high volume; LV, low volume; MSF, musculoskeletal fitness; MICT, moderate-intensity continuous training; RPE, rate of perceived exertion; VICT, vigorous-intensity continuous training; VT2, second ventilatory threshold; WB-HIIT, whole-body high-intensity interval training; WB-MIIT, whole-body moderate intensity interval training; Wmax, maximal workload, wk(s), week(s), *, excluded from the meta-analysis.