Table 5.
Studies included in the systematic review of the effect of melatonin supplementation on circulating health biomarkers and sports performance tests.
| First Author, Year of Publication and Country (Reference) | Study Design | Characteristics of Participants: Baseline Sample (n, Sex, and Sport Discipline), Age (Mean ± SD), Anthropometric Parameters (Height, Weight, BMI, Body Fat and Muscle Mass) (Mean ± SD), Maximal Oxygen Consumption/Maximal Aerobic Speed (Mean ± SD) and Withdrawals | Intervention | Outcomes | Results IG vs. CG |
|---|---|---|---|---|---|
| Beck et al., 2018, Brazil [38] | Randomized, double-blind, placebo-controlled crossover trial | 11 ♂ trained athletes in multiple sports (soccer, handball, basketball, cycling) Age: 24.18 ± 3.92 years Height: 182 ± 5 cm Weight: 87.07 ± 12.48 kg BMI: 26.18 ± 3.63 kg/m2 Body Fat: 16.28 ± 5.77% Study withdrawals: 0 |
Melatonin: 6 mg tablets (2 mg calcium, 55 mg phosphorus) (Optimum Nutrition, Inc., Downers Grove, IL, USA) Placebo: same conditions with no melatonin 30 min before exercise 1 day 06:00–09.00 p.m. Washout period: 48 to 72 h |
RCB Hemoglobin Hematocrit WBC Neutrophils Lymphocytes Monocytes Uric Acid Urea Creatinine Total Proteins Glucose Total cholesterol Triglycerides CK LDH Time to exhaustion test |
↔ RCB ↔ Hemoglobin ↔ Hematocrit ↔ WBC ↔ Neutrophils ↔ Lymphocytes ↔ Monocytes ↔ Uric Acid ↔Urea ↔ Creatinine ↔ Total Proteins ↔ Glucose ↓ * Total cholesterol ↔ Triglycerides ↔ CK ↔ LDH ↑ * Time to exhaustion test |
| Brandeberger et al., 2018, USA [39] | Randomized, double-blind, placebo-controlled, crossover trial | 10 ♂ endurance-trained cyclists Age: 25.1 ± 4.0 years Height: 176 ± 7.1 cm Body Fat: 9.2 ± 13.2% VO2max: 62.7 ± 6.3 mL/kg/min Study withdrawals: 0 |
Melatonin: 5 mg Tablets (NR) Placebo: (multivitamin) similar size and shape to the melatonin 15 min before exercise 1 day 02:00–06.00 p.m. Washout period: ≥7 days |
Rectal temperature RPE Medium Power Average Cycling Cadence 32.2 km cycling time trial |
↔ Rectal temperature ↔ RPE ↔ Medium Power ↔ Average Cycling Cadence ↔ 32.2 km cycling time trial |
| Cheikh et al., 2018, France [40] | Randomized, double-blind, placebo-controlled crossover trial | 10 ♂ national-level judo competitors (currently training ~8 h/week) Age: 15.4 ± 0.3 years Weight: 60.6 ± 5.7 kg Height: 167.9 ± 6.9 cm BMI: 21.21 ± 2.5 kg/m2 Study withdrawals: 0 |
Melatonin: 10 mg Tablets MEL-10 mg (Jamieson lab Toronto, Montreal, Vancouver, Canada N8W5B5) Placebo: starch and cellulose 2 h after exercise (15 min before bedtime) 1 day 10:00 p.m. Washout period: 7 days |
RPE Hooper index (Fatigue) YYIRT-1 Manual pressure force 5-Jump Test Vertical jump Horizontal jump |
↓ * RPE ↓ Hooper Index ↑ * YYIRT-1 ↔ Manual pressure force ↑ 5-Jump Test ↔ Vertical jump ↔ Horizontal jump |
| Cheikh et al., 2020, France [41] | Randomized, double-blind, placebo-controlled crossover trial | 14 ♂ volleyball players from Tunisian league 1 (training 4 days per week for an average of 1.5–2 h) Age: 14.5 ± 0.52 years Weight: 65.68 ± 7.72 kg Height: 181.57 ± 7.38 cm BMI: 21.21 ± 2.5 kg/m2 Study withdrawals: 0 |
Melatonin: 10 mg Tablets MEL-10 mg (Jamieson lab Toronto, Montreal, Vancouver, Canada N8W5B5) Placebo: starch and cellulose 2 h after exercise (15 min before bedtime) 1 day 10:00 p.m. Washout period: 7 days |
WBC Neutrophils Lymphocytes CK LDH AST CRP MDA Homocysteine Fatigue Inex Medium Power Peak Power Time trial |
↓ * WBC ↓ * Neutrophils ↓ * Lymphocytes ↓ * CK ↓ * LDH ↓ * AST ↓ * CRP ↓ * MDA ↓ *Homocysteine ↓ * Fatigue Inex ↑ * Medium Power ↑ * Peak Power ↓ * Time trial |
| Czucejko et al., 2019, Poland [42] | Randomized, double-blind, placebo-controlled, parallel group trial | 81 ♂ and ♀ IG: 47 ♀ second and third league soccer players (Zawisza Bydgoszcz Sports Club, Bydgoszcz, Poland), 19 ♂ rowers (Bydgoszcz Rowing Club, Poland); CG 15 ♂ non-training young adults Melatonin Group: Age: 20.95 ± 2.5 years Weight: 89.7 ± 8.5 kg Height: 1.85 ± 0.2 m BMI: 26.2 ± 0.2 kg/m2 Control Group: Age: 20.50 ± 2.0 years Weight: 82.1 ± 6.5 kg Height: 1.82 ± 0.11 m BMI: 24.8 ± 0.1 kg/m2 Study withdrawals: 0 66 participants in IG 15 participants in CG |
Melatonin: Orally in a single dose 5 mg melatonin (NR) daily Placebo: NR 1 h before bedtime 30 days No adverse effects were reported |
Glucose IL-6 CRP MDA 8-iso-PGF2α Isoprostane Ox-LDLs SOD GRd GSH GPx Melatonin |
↓ * Glucose ↓ * IL-6 ↓ * CRP ↓ * MDA ↓ * 8-iso-PGF2α Isoprostane ↓ * Ox-LDLs ↔ SOD ↓ * GRd ↑ * GSH ↔ GPx ↑ Melatonin |
| Farjallah et al., 2018, Tunisia [43] | Randomized, double-blind, placebo-controlled crossover trial | 15 ♀ elite athletes (Tunisian handball national team) Age: 17.4 ± 0.4 years Weight: 76.4 ± 5.6 kg Height: 176.0 ± 4.2 cm Study withdrawals: 0 |
Melatonin: 6 mg Tablets quick release (Jamieson Laboratories Toronto, Montreal, Canada) Placebo: lactose, starch, and cellulose 30 min before exercise 4:00 and 4:30 p.m. 1 day Washout period: 2 weeks |
Glucose RPE Blood Lactate Modified agility T-test Squat jump Counter movement jump Maximum standing ball throw velocity test Maximum jump ball throw velocity test 20-m sprint |
↓ * Glucose ↔ RPE ↓ * Blood Lactate ↔ Modified agility T-test ↔ Squat jump ↔ Counter movement jump ↔ Maximum standing ball throw velocity test ↔ Maximum jump ball throw velocity test ↔ 20-m sprint |
| Farjallah et al., 2022, Tunisia [44] | Randomized, double-blind, placebo-controlled, parallel group trial | 24 ♂ professional soccer players from Tunisian first league Age: 18.8 ± 1.3 years Weight: 70.0 ± 10.6 kg Height: 181 ± 8 cm BMI: 21.27 ± 1.87 kg/m2 Study withdrawals: 4 10 participants in IG 10 participants in CG |
Melatonin: 5 mg Capsules (Jamieson Laboratories Toronto, Montreal, Canada) Placebo: lactose, starch, and cellulose After exercise 6 days 7.00 p.m. |
Creatinine Urea Glucose Total Cholesterol HDL LDL Triglycerides Total Proteins γ-glutamyl transferase Alkaline Phosphatase CK AOPP SOD Squat jump Countermovement jump 5-jump test Modified agility T-test 20-m sprint |
↓ Creatinine ↓ Urea ↔ Glucose ↔ Total Cholesterol ↔ HDL ↔ LDL ↔ Triglycerides ↔ Total Proteins ↓ γ-glutamyl transferase ↓ Alkaline Phosphatase ↓ CK ↓ AOPP ↑ * SOD ↑ Squat jump ↑ Countermovement jump ↑ 5-jump test ↓ Modified agility T-test ↓ 20-m sprint |
| Farjallah et al., 2023, Tunisia [45] | Randomized, double-blind, placebo-controlled, parallel group trial | 12 ♂ professional soccer players from Tunisian first league (soccer experience from 5–7 years) Age: 17.54 ± 0.78 years, Weight: 70.31 ± 3.86 kg Height: 1.80 ± 0.08 m Maximal Aerobic Speed: 16.85 ± 0.63 km/h Study withdrawals: 0 |
Melatonin: 6 mg Tablets quick release (Jamieson Laboratories Toronto, Montreal, Canada) Placebo: lactose, starch, and cellulose 30 min before exercise 5:00 ± 0:30 p.m. 1 day Washout period: 48 h |
WBC Neutrophils Lymphocytes Monocytes Glucose Total Cholesterol HDL LDL Triglycerides Creatinine Urea Total Proteins AST ALT γ-glutamyl transferase Alkaline Phosphatase Blood Lactate Heart Rate Time to exhaustion Distance covered |
↔ WBC ↔ Neutrophils ↔ Lymphocytes ↔ Monocytes ↔ Glucose ↔ Total Cholesterol ↔ HDL ↔ LDL ↔ Triglycerides ↓ * Creatinine ↔ Urea ↔ Total Proteins ↓ * AST ↓ * ALT ↓ * γ-glutamyl transferase ↓ Alkaline Phosphatase ↔ Blood Lactate ↓ Heart Rate ↑ Time to exhaustion ↑ Distance covered |
| Farjallah et al., 2022, Tunisia [46] | Randomized, double-blind, placebo-controlled crossover trial | 13 ♂ professional soccer players from Tunisian first league Age: 17.5 ± 0.8 years Weight: 70.0 ± 3.9 kg Height: 180 ± 8 cm Maximal Aerobic Speed: 16.85 ± 0.63 km/h Study withdrawals: 0 |
Melatonin: 6 mg Capsules (Jamieson Laboratories Toronto, Montreal, Canada) Placebo: lactose, starch, and cellulose 10 min after exercise 1 day 05.00 p.m.–00.30 a.m. Washout period: 2 days |
Uric Acid Total Bilirubin CK LDH MDA AOPP SOD GPx GRd RPE Running exercise test |
↓ Uric Acid ↓ Total Bilirubin ↓ CK ↓ LDH ↓ MDA ↓ AOPP ↑ SOD ↑ GPx ↔ GRd ↔ RPE ↔ Running exercise test |
| Farjallah et al., 2020, Tunisia [47] | Randomized, double-blind, placebo-controlled, parallel group trial | 20 ♂ professional soccer players from Tunisian first league Age: 18.9 ±1.3 years Weight: 70.1 ± 10.6 kg Height: 180 ± 1.0 cm Study withdrawals: 0 10 participants in IG 10 participants in CG |
Melatonin: 5 mg Capsules (Jamieson Laboratories Toronto, Montreal, Canada) Placebo: lactose, starch, and cellulose After exercise 6 days 7.00 p.m. |
CK LDH MAD SOD VAS Repeated sprint ability test |
↓ * CK ↓ * LDH ↓ * MAD ↑ * SOD ↓ * VAS ↓ Repeated sprint ability test |
| Ghatassi et al., 2016, Tunisia [48] | Randomized, double-blind, placebo-controlled crossover trial | 12 ♂ soccer players (Tunisian League 3) Age: 17.9 ± 1.3 years Weight: 62.0 ± 8.8 kg Height: 174 ± 6 cm |
Melatonin: 5 mg Capsules (Jamieson Laboratories Toronto, Montreal, Canada) Placebo: lactose, starch, and cellulose 30 min before exercise 1 day 07.30 a.m. Washout period: 36 h |
Medicine-ball throw Manual pressure force 5-jump test Agility T-test Reaction time Vigilance tests |
↑ * Medicine-ball throw ↑ * Manual pressure force ↔ 5-jump test ↔ Agility T-test ↓ * Reaction time ↓ * Vigilance tests |
| Ghatassi et al., 2024, Tunisia [49] | Randomized, double-blind, placebo-controlled crossover trial | 12 ♂ soccer players (Tunisian League) Age: 22.9 ± 1.3 years Weight: 72.0 ± 8.8 kg Height: 1.80 ± 0.05 m |
Melatonin: 5 mg Capsules (Jamieson Laboratories Toronto, Montreal, Canada) Placebo: lactose, starch, and cellulose 30 min before exercise 1 day 07.30 a.m. Washout period: 48 h |
Glucose Hooper’s index Manual pressure force Squat jump RPE Reaction time Vigilance Test Blood lactate Peak Power Average Power Modified agility T-test |
↔ Glucose ↓ Hooper’s index ↑ Manual pressure force ↑ Squat jump ↓ RPE ↓ Reaction time ↔ Vigilance Test ↔ Blood lactate ↑ Peak Power ↑ Average Power ↔ Modified agility T-test |
| Ghatassi et al., 2014, Tunisia [50] | Randomized, double-blind, placebo-controlled crossover trial | 12 ♂ soccer players (Tunisian League 3) Age: 17.9 ± 1.3 years Weight: 62.0 ± 8.8 kg Height: 174 ± 6 cm |
Melatonin: 5 mg or 8 mg Capsules (Jamieson Laboratories Toronto, Montreal, Canada) Placebo: lactose, starch, and cellulose 30 min before exercise 07.30 a.m. 1 day Washout period: NR 3 test sessions at 9:00 p.m. on different days |
Medicine-ball throw Manual pressure force 5-jump test Squat jump Counter movement jump Agility T-test Reaction time Vigilance tests |
Melatonin: 5 mg ↔ Medicine-ball throw ↑ Manual pressure force ↔ 5-jump test ↔ Squat jump ↔ Counter movement jump ↔ Agility T-test Melatonin: 8 mg ↓ Medicine-ball throw ↓ * Manual pressure force ↓ 5-jump test ↓ * Squat jump ↓ * Counter movement jump ↔ Modified agility T-test |
| Khaleghi-Mamaghani et al., 2021, Turkey [51] | Randomized, double-blind, placebo-controlled crossover trial | 10 ♂ highly trained (3–4 days per week for an average of 2-h training in a day) Age: 23.4 ± 1.71 years Weight: 74.28 ± 6.69 kg Height: 176 ± 6.42 cm BMI: 23.96 ± 1.63 kg/m2 Body Fat: 13.4 ± 2.75% |
Melatonin: 10 mg (NR) Placebo: (NR) 30 to 45 min after exercise 1 day 11.00 a.m. Washout period: 1 week |
Heart Rate DBP SBP Blood Lactate Reaction time Dynamic balance Static balance Jump strength Manual pressure force Squat Bench press Anaerobic peak power Anaerobic minimum power Average power Fatigue index |
↓ Heart Rate ↓ DBP ↓ SBP ↓ Blood Lactate ↑ Reaction time ↑ Dynamic balance ↑ Static balance ↔ Jump strength ↔ Manual pressure force ↔ Squat ↔ Bench press ↓ Anaerobic peak power ↓ Anaerobic minimum power ↓ Average power ↓ Fatigue index |
| Leonardo-Mendonça et al., 2017, Spain [52] | Randomized, double-blind, placebo-controlled, parallel group trial | 24 ♂ resistance-trained athletes Age: 20.3 ± 0.71 years Weight: 74.7 ± 3.22 kg Height: 176.7 ± 1.83 cm Study withdrawals: 0 12 participants in IG 12 participants in CG |
Melatonin: 100 mg per day gelatinous capsules (NR) Placebo: capsules excipients (lactose, colloidal silica) 30 min before bedtime 4 weeks |
RCB Hemoglobin Hematocrit Leukocyte Glucose Total Cholesterol Triglycerides Creatinine Urea Uric Acid CK LDH AST ALT AOPP Lipid peroxidation ORAC Nitrites GSH GSSG GSH:GSSG GPx GRd GPx:GRd |
↔ RBC ↔ Hemoglobin ↔ Hematocrit ↔ Leukocyte ↔ Glucose ↓ * Total Cholesterol ↔ Triglycerides ↓ Creatinine ↔ Urea ↔ Uric Acid ↓ * CK ↓ * LDH ↔ AST ↔ ALT ↓ * AOPP ↓ * Lipid peroxidation ↑ * ORAC ↓ * Nitrites ↔ GSH ↓ * GSSG ↓ * GSH:GSSG ↓ * GPx ↓ * GRd ↓ * GPx:GRd |
| Maldonado et al., 2012, Spain [53] |
Randomized, single-blind, placebo-controlled, parallel group trial | 16 ♂ professional active soccer players (from the Sevilla football club of the second division of Spain, belonging to the Spanish Professional Football League) Age (Range): 18–20 years Weight: 68.2 ± 1.5 kg Height: 177.2 ± 6.9 cm Study withdrawals: 0 8 participants in IG 8 participants in CG |
Melatonin: 6 mg (NR) Placebo: (NR) 30 min before exercise 1 day |
RCB Hemoglobin Hematocrit WBC Neutrophils Lymphocytes Natural Killer Ig M Ig G Ig A Cortisol Testosterone Glucose Total Cholesterol Triglycerides Total Proteins Creatinine Urea Uric Acid CK LDH AST ALT MDA TAS |
↔ RCB ↔ Hemoglobin ↔ Hemoglobin ↔ WBC ↔ Neutrophils ↔ Lymphocytes ↔ Natural Killer ↔ Ig M ↔ Ig G ↑ * Ig A ↔ Cortisol ↔ Testosterone ↔ Glucose ↔ Total Cholesterol ↓ * Triglycerides ↔ Total Proteins ↔ Creatinine ↔ Urea ↔ Uric Acid ↔ CK ↔ LDH ↔ AST ↔ ALT ↓ * MDA ↑ * TAS |
| Mero et al., 2006, Finland [54] | Randomized, double-blind, placebo-controlled crossover trial | 10 ♂ high strength and resistance-trained (regular exercise four times a week with 4.8 ± 2.0 years’ experience in strength and resistance training) Age: 24.0 ± 3.0 years Weight: 74.7 ± 5.4 kg Height: 178.0 ± 5.0 cm Body Fat: 14.3 ± 3.4% Study withdrawals: 0 |
Melatonin: 6 mg Tablets (University of Pharmacy, Finland), Placebo: 6 mg Tablets 60 min before exercise 1 day Washout period: 14 days |
Glucose Cortisol Testosterone Grow Hormone Lactate Counter movement jump Squat Bench press Resistance Exercise Serum melatonin |
↔ Glucose ↔ Cortisol ↔ Testosterone ↔ Grow Hormone ↔ Lactate ↔ Counter movement jump ↔ Squat ↔ Bench press ↔ Resistance Exercise ↑ * Serum melatonin |
| Ochoa et al., 2011, Spain [55] | Randomized, double-blind, placebo-controlled, parallel group trial | 20 ♂ highly trained athletes daily (running) Characteristics of participants NR Study withdrawals: 0 8 participants in IG 8 participants in CG |
Melatonin: 5 capsules 3 mg (Natrol, Chatsworth, CA, USA) Total dose 15 mg 1 capsule 2 days before the test with dinner, 3 capsules on the previous day (breakfast, lunch, and dinner), 1 capsule the same day of the run, 1 h before physical exercise test Placebo: beer yeast, cellulose, acacia, silica stearic acid, magnesium stearate, cellulose gum, maltodextrin 3 days |
RBC Hemoglobin Reduction plasma viscosity Cholesterol Phospholipids Total Bilirubin Total Proteins Creatinine TNF-α IL-6 sTNF-α-RII IL-1ra TAS 15-F2t-Isoprostane 8-OHdG CAT GPx Serum melatonin |
↔ RBC ↔ Hemoglobin ↔ Reduction plasma viscosity ↓ Cholesterol ↓ Phospholipids ↓ Total Bilirubin ↔ Total Proteins ↓ Creatinine ↓ * TNF-α ↓ * IL-6 ↑ sTNF-α-RII ↑ * IL-1ra ↑ * TAS ↓ 15-F2t-Isoprostane ↓ 8-OHdG ↑ * CAT ↑ * GPx ↑ * Serum melatonin |
| Ortiz-Franco et al., 2017, Spain [56] | Randomized, double-blind, placebo-controlled, parallel group trial | 14 ♂ highly trained athletes Age: CG: 28.43 ± 4.39 years IG: 26.00 ± 6.03 years Weight: CG: 78.39 ± 6.68 kg IG: 79.96 ± 7.29 kg Height: CG: 176.9 ± 3.89 cm IG: 179.9 ± 6.04 cm BMI: CG: 25.06 ± 2.20 kg/m2 IG: 24.70 ± 19.8 kg/m2 Fat Mass: CG: 13.21 ± 3.91 kg IG: 14.79 ± 3.60 kg Muscle Mass: CG: 61.96 ± 4.13 kg IG: 61.94 ± 4.21 kg Study withdrawals: 0 7 participants in IG 7 participants in CG |
Melatonin: 1 daily capsule containing 20 mg of melatonin (Acofarma®, Barcelona, Spain) Placebo: 1 daily capsule containing lactose Before exercise NR 14 days |
RBC Hemoglobin Hematocrit Transferrin Ferritin Serum Iron Glucose Urea Creatinine Uric Acid Total Cholesterol HDL LDL Triglycerides Total Bilirubin Albumin Prealbumin TAC SOD GPx DNA damage Serum melatonin |
↔ RBC ↔ Hemoglobin ↔ Hematocrit ↔Transferrin ↔ Ferritin ↔ Serum Iron ↔ Glucose ↔ Urea ↔ Creatinine ↔ Uric Acid ↔ Total Cholesterol ↔ HDL ↔ LDL ↔ Triglycerides ↔ Total Bilirubin ↔ Albumin ↔ Prealbumin ↑ * TAC ↔ SOD ↑ * GPx ↓ * DNA damage ↑ * Serum melatonin |
| Paryab et al., 2021, Tunisia [57] | Randomized, double-blind, placebo-controlled, repeated-measures crossover trial | 33 ♂ university championship professional athletes (running) Age: 20.0 ± 2.0 years Weight: Body Mass: 83.4 ± 14.4 kg Height: 180.0 ± 1.0 cm Study withdrawals: 23 10 participants in IG/CG |
Melatonin: 6 mg Tablets (NR) Placebo: 6 mg Tablets (NR) 30 min before training 1 day 08:00 a.m. Washout period: 3 days |
Blood Lactate Reaction time Static balance Dynamic balance Anaerobic power |
↓ * Blood Lactate ↓ * Reaction time ↑ * Static balance ↑ * Dynamic balance ↑ * Anaerobic power |
| Souissi et al., 2020 Tunisia [58] | Randomized, double-blind, placebo-controlled crossover trial | 8 ♂ highly trained athletes (students of Institute of Sports and Physical Education) Age: 21.8 ± 0.9 years Weight: NR BMI: 21.0 ± 0.8 kg/m2 Study withdrawals: 0 |
Melatonin: 6 mg Capsules (NR) Placebo: 6 mg Capsules (NR) 50 min before exercise 1 day 09:00 a.m. Washout period: NR 2 test sessions at 8:00 a.m. on different days |
CRP LDH AST ALT |
↔ CRP ↔ LDH ↔ AST ↔ ALT |
Symbols and abbreviations: ↑ = no significant increase; ↓ = no significant decrease; ↔ = no significant change. ↑ * = significant increase; ↓ * = significant decrease; *: indicates significant values (p < 0.05); ♂ = men. ♀ = women. 8-OHdG = 8-hydroxy-2-deoxyguanosine; ALT = alanine aminotransferase; a.m. = ante meridiem; AOPP = advanced oxidation protein products; AST = aspartate aminotransferase; BMI = body mass index; CAT = catalase; DBP = diastolic blood pressure; CG = control group; CK = creatine kinase; CRP = C-reactive protein; GPx = glutathione peroxidase; GRd = glutathione reductase; GSH = Reduced Glutathione; GSSG = oxidized glutathione; HDL = high-density lipoprotein; IG = intervention group; Ig = immunoglobulin; IL: interleukin; IL1-ra = IL-1 receptor antagonist; LDH = lactate dehydrogenase; LDL = low-density lipoprotein; MDA = malondialdehyde; min = minutes; NR = no reported; ORAC = Oxygen radical absorption capacity; ox-LDLs = oxidized low-density lipoprotein molecules; p.m. = post meridiem; RCB = red blood cells; RPE = rating of perceived exertion; SBP = systolic blood pressure; SD = standard deviation; SOD = superoxide dismutase; sTNF-α-RII = soluble receptor II of TNF-α; TAC = total antioxidant capacity; TAS = total antioxidant status; TNF-α = tumor necrosis factor-α; VAS = visual analogue scale; VO2max = maximum oxygen consumption; WBC = white blood cells; YYIRT-1 = Yo-Yo intermittent recovery test level 1.