Table 1.

Exercise protocols of the studies included in the analysis.

Sijie (2012)50	-5x/week during 12 weeks. -HIIT: 5x3-min interval running at the individualized HR of 85% of VO2 max which was intervened by a 3-min active break in between at the individualized HR of 50% of VO2 max. -CAT: Continuous walking and/or jogging at the individualized HR of 50% of VO2 max for 40 min.
Gripp (2020)43	-2x/week during 8 weeks. -The training programs were based on the maximum velocity achieved during the 20 m shuttle test (Vshuttle). -After 4 weeks of training, participants performed a new 20 m shuttle test for the adjustment of the speed of the training program. -HIIT: Participants ran 7–10x, 200 m at 85–100% of Vshuttle, during 14–19 min/session. -CAT: Participants ran 3500–5000 m at 60–75% of Vshuttle, during 27–32 min/session.
Keating (2014)46	-3x/week (60–72 min/week total training time) during 12 weeks -HIIT: exercise on the cycle ergometer at a power output designed to 120% of VO2 peak; they performed 4-6x in 30–60 s on work + 180-120 s of recovery at low intensity. -CAT: continuous cycling on the ergometer 30–45 min at 50–65% VO2 peak.
Zhang (2017)51	-3x/week, during 12 weeks. -A continuous 60 rpm during each training session in both groups was observed. -HIIT: participants repeated 4-min cycling exercise bouts at an intensity of 90% VO2 max, followed by a 3-min passive recovery until the targeted 300 kJ of work was achieved. -CAT: participants performed continuous exercise on a cycle ergometer at an intensity of 60% VO2 max until the targeted 300 kJ of work was achieved.
Cooper (2016)42	-3x/week, during 12 weeks. -Exercise was performed in a cycle ergometer. -HIIT active rest: the protocol is comprised of 4–10 intervals efforts with 1:6 (work:rest) cycles, via 30 s sprint efforts (120 rpm) followed by 3 min of passive recovery. -HIIT passive rest: the protocol is comprised of 4–10 intervals efforts with 1:6 (work:rest) cycles, via 30 s sprint efforts (120 rpm), followed by 3 min of periods involving continued cycling at 60 rpm at a lightened resistance. -CAT: the program consisted of cycle ergometry at ∼80–85% of age-predicted HR max, during 50–60 min/session.
Hornbuckle (2018)45	-3x/week, during 16 weeks. -Treadmill walking with 4 weeks of adaptation period for both groups (20–25 min at 60–70% HR max). -HIIT: the protocol is comprised of 7 × 1 min at 80–90% HR max +3 min at 60–70% HR max of recovery at low intensity. -CAT: participants performed a continuous exercise at 60–70% HR max during 32 min.
Ram (2020)48	-3x/week during 6 weeks. -All training was conducted on manual-resistance cycle ergometers. -HIIT: the program consisted of 10 × 1 min intervals at ∼90% HR peak, with 1 min active recovery intervals at a low workload. -CAT: the protocol consisted of 30 min of continuous exercise at 65–75% of HR peak.
Higgins (2016)44	-3x/week during 6 weeks. -All sessions were performed on a friction-loaded stationary cycle ergometer. -HIIT and CAT were performed with equal estimated energy expenditure during training. -HIIT: 5–7 sprints of 30-s with “all out” intensity interspersed with 4 min of active recovery pedaling against minimal resistance at a low pedal frequency. This exercise stimulus equated to 2.5–3.5 min of near-maximal effort interspersed with 16–28 min of recovery. -CAT: participants were instructed to cycle continuously at an intensity of 60–70% HR reserve for 20–30 min, with the duration of training sessions systematically increased to maintain equal estimated energy expenditure between groups.
Kong (2016)47	-4x/week during 5 weeks. -All sessions were performed on a stationary cycle ergometer. -HIIT: the participants performed 60x of 8 s cycling +12 s passive recovery for 20 min. -CAT: the group performed a continuous cycling exercise at 65% of VO2 peak for 40 min. A cycling speed of 60 ± 5 rpm would be maintained throughout each training session.
Zhang (2021)52	-Four-cycle ergometer training regimens was performed during 12 weeks. -HIIT 90: repeat 4-min exercise at 90% VO2 peak, followed by a 3-min passive recovery, until the targeted 200 kJ of work was achieved. -HIIT 120: repeat 1-min exercise at 120% VO2 peak, followed by a 1.5-min passive recovery, until the targeted 200 kJ of work was achieved. -All-HIIT: 40 bouts of 6 s at all-out effort, followed by a 9 s of passive recovery. -CAT: continuous exercise at 60% VO2 peak until the targeted 200 kJ of work was achieved.
Rowley (2017)49	-3x/week during 12 weeks. -The researchers worked with maximal speed that participants could maintain for the full 30 s and that would elicit a maximal or near maximal HR response. -HIIT: participants completed 4 × 30 s sprints at a 3–5% grade on treadmill, and the sprints were paired with a 4 min walking recovery at 2.5 mph and 0% grade. -CAT: participants walked or jogged continuously for 30–60 min (with an increase of 10 min every 3 weeks) on a treadmill at a 3–5% grade at an intensity of their individual 45–55% HR reserve.

HR, heart rate; VO₂, oxygen consumption volume; HIIT, high-intensity interval training; CAT, continuous aerobic training.