Table 1 Summary of the results obtained in studies examining the impacts of beetroot juice supplements on intermittent high intensity exercise performance

Muggeridge et al. [38]

Trained kayakers (male, n = 8) (VO_2peak 49.0 ± 6.1 ml·kg·min⁻¹)

Single-blind, randomized, cross-over

5 mmol NO₃⁻ (180 min before)

Kayak ergometer: 5 × 10 s sprint-rest 50 s

+4% average power (420 ± 23 vs 404 ± 24 W)

Martin et al. [53]

Recreation team sport players (male,n = 16) (VO_2peak 47.2 ± 8.5 ml·kg·min⁻¹)

Double-blind, randomized, cross-over

6.4 mmol NO₃⁻ (120 min before)

Cycle ergometer: sets until exhaustion of 8 s– rest 30 s

−13% reps (13 ± 5 vs 15 ± 6) and −17% total work (49.2 ± 24.2 vs 57.8 ± 34.0 kJ)

Aucouturier et al. [54]

Recreation team sport players (male, n = 12) (VO_2peak 46.6 ± 3.4 ml·kg·min⁻¹)

Single-blind, randomized, cross-over

10.9 mmol NO₃⁻ (180 min before)

Cycle ergometer: sets until exhaustion of 15 s at 170% MAP–rest 30 s

+20% reps^* (26.1 ± 10.7 vs 21.8 ± 8.0) and 18% total workload^* (168.2 ± 60.2 vs 142.0 ± 46.8 kJ)

Buck et al. [55]

Amateur team sport players (female, n = 13) (VO_2peak not specified)

Double-blind, randomized, Latin-square

BJ: 6.4 mmol NO₃⁻ (6 days) BJ + SP: 6.4 mmol NO₃⁻ + 50 mg·kg lean mass SP (6 days)

PRE, MID and POST simulation team sport matches: 6×(20 m sprint + rest 25 s)

BJ: −0.2% total sprint time per set (69.8 ± 4.9 vs 69.97 ± 4.2) BJ + SP: −2% total sprint time per set (68.9 ± 5.1 vs 69.97 ± 4.2)

Thompson et al. [56]

Recreation team sport players (male, n = 16) (VO_2peak 50 ± 7 ml·kg·min⁻¹)

Double-blind, randomized, cross-over

12.8 mmol NO₃⁻ (7 days)

MID and POST simulated team-sport matches: 2×[5×(6 s cycle ergometry sprint + rest 14 s)]

5% work volume at MID^* (63 ± 20 vs 60 ± 18 kJ), 2% POST (60 ± 17 vs 59 ± 16 kJ) and 4% whole session^* (123 ± 19 vs 119 ± 17 kJ)

Clifford et al. [57]

Competition team sport players (male, n = 20) (VO_2peak not specified)

Double-blind, independent groups design

11.4 mmol NO₃⁻ (150 min before)

2xRST: 20×(30 m sprint–rest 30 s)

-1% average sprint time RST1 (4.65 ± 0.3 vs 4.7 ± 0.2 s) and −2% RST2 (4.66 ± 0.2 vs 4.77 ± 0.2 s) and −2% fastest sprint RST1 (4.41 ± 0.2 vs 4.48 ± 0.1 s) and −3%RST2 (4.38 ± 0.2 vs 4.53 ± 0.2 s)

Mosher et al. [58]

Recreation sport players (male, n = 12) (VO_2peak not specified)

Double-blind, randomized, cross-over

6.4 mmol NO₃⁻ (6 days)

Bench press: 3×(maximum number reps at 60% 1 RM)

+ 19% weight lifted in session and improved no. of reps S1^*, S2^*, S3^* and whole session. ^*improvements not specified

Rimer et al. [59]

Competition sport players (male, n = 13) (VO_2peak not specified)

Double-blind, randomized, cross-over

11.2 mmol NO₃⁻ (150 min before)

Isokinetic cycle ergometer: Wingate 30-s test

-1% peak power (1173 ± 255 vs 1185 ± 249 W) and −1% total work (22.8 ± 4.8 vs 23 ± 4.8 W)

Wylie et al. [60]

Recreation team sport players (male, n = 10) (VO_2peak 58 ± 8 ml·kg·min⁻¹)

Double-blind, randomized, cross-over design

8.4 mmol NO₃⁻ (5 days)

Cycle ergometer: 24 x (6 s sprint–rest 24 s) Cycle ergometer: 7 x (30 s sprint–rest 4 min) Cycle ergometer: 6 x (60 s sprint–rest 60 s)

+5% mean average power^* (568 ± 136 vs 539 ± 136 W) and +1% mean peak power (792 ± 159 vs 782 ± 154 W) in 24 x (6 s sprint–rest 24 s);−1% mean average power (558 ± 95 vs 562 ± 94 W) and −1% mean peak power (768 ± 157 vs 776 ± 142 W) in 7 x (30 s sprint–rest 4 min)