Table 1.
Studies included in the meta-analysis.
| Reference | Sample size (male/female) | Fitness | Age (yr.) M ± SD | BDNF collection | Exercise characteristics (duration/frequency/mode) | Protocol | HIIT classification (by Wen et al. 2019) | Main findings | TESTEX score |
|---|---|---|---|---|---|---|---|---|---|
| Cabral-Santos et al. 2016 | 10 (10/0) | Physically active | 25.2 ± 1.7 | Serum | Crossover acute high-intensity exercise/motorized treadmill | High (2.5 km) and low (1.25 km) session at 1:1 min VO2max velocity with passive recovery | Acute moderate-volume and moderate-interval | Both protocols increased BDNF concentrations. Nonetheless, the BDNF response was not dependent of exercise volume | 7 |
| DiBattista et al. 2018 | 11 (11/0) | Physically active | 28.8 ± 5.3 | Plasma | Acute and after 2 weeks/three times a week/cycle-ergometer | 3-min warm-up at 50 W, 8 × 60 s intervals in sessions 1–2, 10 × 60 s intervals in sessions 3 – 4, 12 × 60 s intervals in sessions 5 – 6 at Wpeak interspersed 75 s of active recovery and 3 min cool-down at 50 W | Short-term, moderate-volume and moderate-interval HIIT | Both first and last session increased BDNF concentrations immediately after the exercise session, ST-HIIT did not change BDNF levels at baseline | 6 |
| Figuereido et al. 2019 | 11 (11/0) | Physically active | 22.5 ± 5.4 | Serum | Acute and eight week intervention/motorized treadmill | 5-min warm-up at 50% VO2max speed, 60 s 100% sVO2max with 60 s passive recovery (no exercise) until completion of 5 km | Acute, high-volume, moderate-interval HIIE | BDNF levels increased after the session completion compared at baseline | 5 |
| Gmiat et al. 2017 | 14 (0/14) | Sedentary | 30.8 ± 18.6 | Serum | Acute high intensity exercise/whole body circuit | 3 × 30 s of AMRAP of 10 circuit whole body exercises (i.e., jumping jacks, push-ups, abdominal crunch, squat, plank, triceps dips, high knees/running, lunges, push-up with rotations and side plank) with 2-min recovery between sets | Acute, high-volume, short-interval HIIE | noted decrease of BDNF after 1 h HIIE was present in both young and middle age participants | 7 |
| Heibisz et al. 2018 | 26 (17/9) | Sportsmen | 19.2 ± 5.2 | Serum | 6 months/2 – 3 sessions a week/cycle-ergometer |
HIIT: 5 to 7 5-min bouts at 85 – 95% Pmax with 12-min of moderate activity efforts at 55 – 60% Pmax 2 × a week SIT: 3 × 3 to 4 30 s bouts at all-out effort with 90 s of active recovery at 50 W and 25-min of low effort (45 – 55% Pmax) between sets |
HIIT: Long-term, high-volume, Long-interval training SIT: Long-term, moderate-volume, SIT |
Decreases of BDNF concentrations 10 and 60 min after sprint test in the SIT group after 2 and 6 month intervention | 11 |
| Heisz et al. 2017 | 66 (24/42) | Sedentary | 20.7 ± 2.8 | Serum | 6 weeks/~ 3 times a week/cycle-ergometer | 3-min warm-up at 50 W, 10 × 60 s of high intensity bouts performed at ~ 80%Wmax/~ 85 – 95% HRpeak combined with 60 s active recovery at ~ 30%Wmax and 2-min cool-down at 50 W | Mid-term, moderate-volume, moderate-interval HIIT | BDNF did not significantly change from the intervention, however individual differences between low and high responders to exercise are directly related to the increase of BDNF concentrations | 11 |
| Kujach et al. 2019 | 36 (36/0) | Physically active | 21.3 ± 1.3 | Serum | Acute/cycle-ergometer | 5-min warm-up at 1.5 W/kg body mass followed by 6 × 30 s all-out bout with fly-wheel at 0.075 kg/kg with resting periods of 4.5-min | Acute, low-volume, SIT | Increase of peripheral BDNF in experimental group was correlated with the significant increase in blood Lactate | 11 |
| Murawska et al. 2015 | 12 (7/5) | Physically active | 25.6 ± 5.8 | Serum | 3 months/2 times a week/CrossFit, whole body workout combined with treadmill or cycling | 60-min of WOD: 15-min strength training (dumbbells and bars) followed with 10-min whole body aerobic exercise circuit and finishing with 15-min of cycling or treadmill | Long-term, high-volume, Long-interval HIIT | Baseline BDNF increased after intervention, then lowered after progressive Wingate test in males but no changes in women | 11 |
| Nicolini et al. 2019 | 18 (18/0) | Sedentary | 23.1 ± | Serum | 6 weeks/3 sessions a week/cycle-ergometer | 3-min warm up at 50% Wpeak, 5 × 60 s high bouts at 105–135% Wpeak with 90 s active recovery at 30% Wpeak | Mid-term, low-volume, moderate-interval HIIT | Improvement of cardiorespiratory fitness but no significant changes in BDNF concentrations after 18 sessions of HIIT in sedentary individuals | 8 |
| Rentería et al. 2019 | 17 (0/17) | Sedentary | 21.5 ± 1.6 | Serum | 4 weeks/3 times a week/cycle-ergometer | 15- to 25-min of 3 to 5 30 s bouts of high intensity at 80% of MAP with 4-min of active recovery at 40% MAP | Mid-term, low-volume, moderate-interval | BDNF concentrations increased after intervention and lowered after graded-exercise test post-HIIT | 7 |
| Reycraft et al. 2019 | 8 (8/0) | Physically active | 23.1 ± 3 | Plasma | Crossover acute training/self-propelled treadmill | 18-min, 4 × 30 s bouts of all-out running interspersed with 4 min of active recovery | Acute, low-volume, SIT | BDNF concentrations were increased immediately post SIT and recovered baseline concentrations 30 and 90 min after exercise, no incremental changes were observed in other modalities | 7 |
| Rodríguez et al. 2018 | 6 (6/0) | Physically active | 22.6 ± 0.7 | Serum | Acute high intensity exercise/motorized treadmill | 5-min warm-up at 50–60%VO2max followed by 4 4 min bouts at 85% VO2max combined with 3-min active recovery at 40%VO2max | Acute/high-volume, long-interval HIIT | Significant BDNF increase after HIIE but the changes were not correlated with the increase in lactate | 7 |
| Sadowska et al. 2019 | 8 (8/0) | Physically active | 23.1 ± 1.7 | Serum | 6 weeks/5 days a week/CrossFit combined with running track field | 50-min of WOD composed with aerobic whole body circuit, aerobic training and weightlifting of predetermined sets or AMRAP | Mid-term, high-volume, combination of repeated sprint and SIT | Slight increase of BDNF levels after CrossFit training, but no changes after aerobic testing were performed | 7 |
| Saucedo-Marquez et al. 2015 | 21 (21/0) | Physically active | 28 ± | Serum | Crossover acute training/cycle-ergometer | 20-min of 60 s at 90% VO2max with 60 s active rest period | Acute, moderate-volume, moderate-interval HIIT | Greater increase of peripheral BDNF in HIIT compared to CON, with a higher magnitude of change in contrast to baseline measures | 11 |
| Slusher et al. 2018 | 13 (13/0) | Sedentary | 23.6 ± 1.0 | Serum and Plasma | Acute high intensity exercise/cycle-ergometer | 5-min, 20 s 170% VO2peak at 5.5% bodyweight interspersed with 10 s active recovery | Acute, low-volume, SIT | Serum BDNF increased significantly after HIIE and remained higher following the completion of executive function test; otherwise plasma BDNF was not modified in either post-HIIE or after completion of executive function text | 7 |
Note: AMRAP: As many repetitions as possible, BDNF: Brain-Derived Neurotrophic Factor. CON: Control group, HIIE: High Intensity Intermittent Exercise, HIIT: High Intensity Interval Training, MAP: Maximal aerobic power, Pmax: Maximal power, SIT: Sprint Interval Training, ST-HIIT: Short-term High Intensity Interval Training, sVO2max: Maximal speed reached during VO2max, VO2max: Maximal oxygen consumption, VO2peak: Peak oxygen consumption, Wmax: Maximal Wattage, WOD: Workout of day, Wpeak: Peak Wattage.