Table 3.

Ergogenic aids interventions in CrossFit® participants.

Study	Sample characteristics	Study design	Intervention			Main findings
			Supplement	Dosage	Timing
Grijota et al. [64]	21 male CrossFit® athletes; training experience: > 2 yrs.	Double-blind crossover trial	Cyclodextrin (CHO derived from plant starch).	30 g	During	– ↔ CrossFit® performance, heart rate, rate of perceived exertion, lactate, glucose execution speed in bench press between groups. – ↑ power values in CHO group. – Average power ↑ in CHO group whilst fatigue index ↑ placebo group.
Główka et al. [65]	26 male and female CrossFit® athletes; training experience: > 2 yrs.	Double-blind crossover trial	Caffeine	3 mg.kgBM−1, 6 mg.kgBM−1, 9 mg.kgBM−1	70 minutes prior to the test	– ↔ of CrossFit® performance (number of repetitions in both groups). − 6 mg.kgBM−1 CAF ↑ number of repetitions. – Heart rate and rate of perceived was ↔ in both groups. – Blood lactate was ↑ in CAF 9 mg.kgBM−1 in comparison to CAF 3 mg.kgBM−1. − 6 mg.kgBM−1 CAF ↓ reaction and motor times.
Durkalec-Michalski et al. [66]	30 male and female CrossFit® participants; training experience: > 4 yrs.	Double-blind crossover trial	Sodium bicarbonate	0.15 g·kg FFM −1, 0.25 g·kg FFM −1. 0. 35 g·kg FFM −1	2 hours prior to exercise	– ↑ blood pH 0.25 g·kg FFM −1 and 0.35 g·kg FFM −1 NaHCO3 to the baseline values at recovery. – ↑ blood pH 0.35 g·kg FFM −1 NaHCO3 at recovery. – Lymphocytes ↑ 0.25 g·kgFFM−1 NaHCO3 post-exercise and recovery than control. – Granulocytes, red blood cells, hemoglobin, white blood cells ↑ control at recovery. – Monocytes ↑ 0.25 g·kgFFM−1 NaHCO3 post-exercise than control at recovery. – Magnesium ↑ in control at recovery. – Creatinine ↓ in control at recovery.
De Souza et al. [67]	17 advanced male CrossFit® trained athletes; training experience: > 1 yr.	Double-blind crossover trial	Sodium bicarbonate	0.30 g·kg−1 ingested with the meal	2 hours prior to exercise	– NaHCO3 ↑ the performance in Fran CrossFit® challenge. – Performance in 500 m rowing and jumping ↔. – NaHCO3 ↑ blood pH in comparison to placebo. – No differences between groups were found for lactate, heart rate and RPE.
Ziyaiyan et al. [68]	20 male CrossFit participants®; training experience: > 2 yrs.	Double-blind crossover trial	Caffeine + sodium bicarbonate	6 mg·kg−1 (CAF) + 0.1 g·kg−1 (NaHCO3)	120, 90, 60 minutes before the protocol	– No significant effects of supplementation were noted. – HRmax ↑ CAF and CAF + NaHCO3 in comparison to control group. – RPE during Cindy challenge ↓ CAF compared to NaHCO3, CAF + NaHCO3 and control groups.
Zawieja et al. [69]	43 male recreationally and regularly trained CrossFit® participants; training experience: > 1 yr.	Double-blind crossover trial	Betaine	2.5 g·kg−1, 5.0 g·kg−1	3 weeks: 2.5 g·kg−1 – three capsules in the morning and two in the evening; 5.0 g·kg−1 – four capsules in the morning, three in the afternoon, and three in the evening	– BET ↑ 8.7% Fight Gone Bad performance but, no significant differences were found compared to placebo group. – ↔ performance in Wingate test in both groups.
Mattos et al. [70]	9 male CrossFit® participants; training experience: > 3 months.	Crossover	CHO	1.0 g·kg−1 grape + banana juice; 1.0 g·kg−1 Whey Maximize	60 minutes before the protocol	– RPE was ↓ on Whey Maximize supplement than fast state.
Oliveira et al. [71]	17 male trained CrossFit® participants; training experience: > 1 yr.	Double-blind crossover trial	Capsiate	12 mg, 24 mg	45 minutes before the protocol	– Performance, HR and RPE was ↔in CAP and placebo.
Martin et al. [72]	11 female CrossFit® athletes; training experience: > 2 yrs.	Double-blind crossover trial	Sodium bicarbonate	0.3 g·kg−1	Individualized approach	– NaHCO3 ↑ 2.2% rowing performance in comparison to placebo group. – Mean power ouput ↑ NaHCO3 (p < 0.05).
Gomes et al. [73]	6 male CrossFit® participants; training experience: > 6 months.	Double-blind parallel trial	Sodium bicarbonate	0.3 g·kg−1	90 – 150 minutes prior to the test	– No effects of NaHCO3 on RPE.
Caetano et al. [74]	8 male trained CrossFit® participants; training experience: > 2 yrs.	Double-blind crossover trial	Caffeine	6 mg·kg−1	60 minutes prior to the protocols	– CAF ↑ local muscular endurance and number of repetitions. – Squat maximum repetition was ↔ in both groups.
Silvestre [75]	19 male and female CrossFit® participants; training experience: > 2 months	Double-blind crossover trial	Beta-alanine	6.4 g.day−1	28 days. 4 times per day: 3 hours of interval (especially after meals)	– No differences between groups in performance, RPE, sleep quality, mood and well-being.
Fernandez-Lázaro et al. [76]	30 trained male CrossFit® participants; training experience: > 3 yrs.	Parallel single-blind trial	Tribulus terrestris	770 mg	6 weeks: 30 minutes prior to CrossFit® workout	– Muscle biomarkers: ↑ LDH in placebo group whilst LDH ↓ in TT supplementation. – Inflammatory markers: ↑ CRP placebo group whilst CRP ↓ in TT supplementation but without significance. – Total Oxidant Status ↑ in TT group. – Performance ↔ in both groups.
Maroufi et al. [77]	8 male CrossFit® athletes; training experience: > 6 months.	Crossover single-blind trial	Carbohydrates + protein	500 ml carbohydrate-protein with different ratios (2:2, 3:1)	60 minutes prior to the test and immediately before	– Performance in CHO + protein and placebo groups was ↔ considering the number of repetitions in CrossFit® challenges.
Fernandez-Lázaro et al. [78]	30 trained male CrossFit® participants; training experience: > 1.5 yrs.	Parallel single-blind trial	Tribulus terrestris	770 mg	6 weeks	– TT ↑ bench press performance significantly whilst the performance in control group ↔. – CrossFit® performance, RPE, hormonal indicators ↔ in both groups.
Toledo et al. [79]	30 male experienced CrossFit® participants; training experience: 2.2 yrs.	Double-blind crossover trial	Sodium bicarbonate	0.3 g·kg−1	60 minutes prior to the test	– Number of repetitions, lactate, average and maximal heart rate, were ↔ in both conditions.
Stein et al. [80]	30 male CrossFit® participants; training experience: > 6 months.	Double-blind crossover trial	Caffeine	5 mg.kg−1	60 minutes prior to the test	– Number of repetitions and RPE ↔ in both groups.
Moro et al. [81]	29 male and female CrossFit® participants; training experience: > 6 months.	Double-blind crossover trial	Betaine	2.50 g (dosages of 1.25 g)	6 weeks: first dosage in morning, second dosage 60 minute before the work	– Significant improvements on back squat were noted for BET. – No differences between groups were found for the remaining performance variables.
Ricordi et al. [82]	18 male and female beginner CrossFit® participants; training experience: > 6 months.	Double-blind crossover trial	Nitrate	10 g.kg−1	2 hours before CrossFit® practice	– CrossFit® performance was ↔ in both groups.
Garnacho-Castano et al. [83]	12 male CrossFit® participants; training experience: > 2 yrs.	Double-blind crossover trial	Beetroot juice	~808 mg	3 hours prior to exercise	– BJ ↑ the number of repetitions (after including resting time in the protocol). – Jumping and blood lactate were ↔in both conditions. – SpO2 decrease was ↑ BJ condition. – Decline in jumping performance was ↑ BJ condition.
Fogaça et al. [84]	9 male experienced CrossFit® participants; training experience: 2 yrs.	Double-blind crossover trial	Caffeine	6 mg.kg−1	60 hours prior to exercise.	– Negligible differences between CAF and placebo groups were found for propulsive and peak power, bench press, jump squat, countermovement jumps and handgrip strength. – RPE and DOMS were ↔ in both groups. – Concentrations of CK and CPR ↔ in post and 24 hours post workout.
Durkalec-Michalski et al. [85]	21 recreational male and female CrossFit® participants; training experience: > 2 yrs.	Double-blind crossover trial	Sodium bicarbonate	Progressive dosages: 150 mg.kg−1. Each 2 days, for 8 days, ↑ 25% of sodium bicarbonate dosage.	10 days: 3 doses per day. Training days was taken 1.5 hours before training sessions.	– Performance in FGB ↑ when participants ingested NaHCO3. – Derived from incremental cycling test, maximum workload and HR were ↔ in both groups. – Workload at ventilatory threshold was 4.6% higher (p < 0.05) in NaHCO3 than placebo. – Time to attain ventilatory threshold was 5.1% higher (p < 0.05) in NaHCO3 than placebo. – HR at ventilatory threshold was significantly higher in NaHCO3 than placebo. – Time to attain ventilatory threshold was 5.1% higher (p < 0.05) in NaHCO3 than placebo. – Pyruvate was significantly higher in NaHCO3 than placebo.
Rountree et al. [86]	8 CrossFit® trained males; training experience: > 3 months.	Double-blind crossover trial	CHO	16 g	Immediately prior and during exercise.	– Performance was ↔ in FGB on both trials.
Howarth et al. [87]	11 CrossFit® athletes; training experience: NR.	Crossover trial	CHO	Ad libitium	During the workout.	– Performance and RPE were ↔ in both groups.
Kramer et al. [88]	12 male CrossFit® athletes; training experience: > 4 months.	Double-blind crossover trial	Nitrate	8 mmol·d−1	6 days. Two times per day: morning and evening.	– No differences between groups were noted for CrossFit® performance (Grace and 2 km rowing). – The trend was maintained for physical performance with the exception of Wingate protocol. – Substantial improvements were noted for the $\mathit{N}{O}_3^{-}$ group (6.6%) on peak power output.
Outlaw et al. [89]	29 male and females CrossFit® participants; training experience: > 6 months.	Crossover	Pre-workout: tart cherry extract, beet root Extract, green tea and black tea extract. Post-workout.	Pre-workout: 19 g Post-workout: females (20 g protein, 40 g CHO), males (40 g protein, 80 g CHO).	6 weeks: prior to the session.	– Performance on Wingate mean power and VO2max ↑ in the supplementation group. – CrossFit® performance↑ on supplementation group but, without statistical significance.
Jacobs et al. [90]	16 male and females CrossFit® participants; training experience: > 6 months.	Crossover	Commercial pre-workout supplement with beta-alanine, grape seed extract, coenzyme Q10, brown rice extract, natural caffeine, vitamins and minerals.	NR	20 minutes prior to Cindy workout.	– Cindy performance ↑ in pre-workout supplement.