In this investigation the investigators utilized NAC supplementation to boost GSH availability during an one-week-microcycle consisting of three soccer games, in order to test the hypotheses that: i) antioxidant supplementation may enhance the recovery of performance and physiological stress variables following multiple match-plays and ii) redox status perturbations are critical in regulating the inflammatory response and repair in skeletal muscle, following repetitive exercise-induced muscle injuries.
After exercise-induced muscle microtrauma the thiol/disulfide couple of reduced (GSH) and oxidized glutathione (GSSG) is a key regulator of important transcriptional pathways that control the inflammatory response and recovery of skeletal muscle. The objective was to examine how thiol-based antioxidant supplementation affects the muscle damage, oxidative stress, inflammatory and immune responses, as well as the level of post-game fatigue and muscle's recovery kinetics in response to three soccer games within a week. Participants were randomly assigned to one of four groups: i) Experimental-NAC \[EXP-NAC, N=10, participated in daily training sessions and three games and received NAC (20 mg/kg/day)\], ii) Experimental-Placebo (EXP-Pla, N=10, participated in daily training sessions and three games and received Placebo), iii) Control-NAC \[CON-NAC, N=10, participated in daily training sessions only and received NAC(20 mg/kg/day)\] and iv) Control-Placebo (CON-Pla, N=10, participated in daily training sessions only and received Placebo). Blood samples were collected at baseline, post-games and daily during recovery. Performance was assessed at baseline and daily during recovery.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
DOUBLE
Enrollment
40
Orally in three daily dosages (morning-midday-evening), at 20 mg/kg/day, for seven consecutive days.
500 mL drink that contained water (375 mL), sugar-free cordial (125 ml), and 2 g of low-calorie glucose/dextrose powder. Orally in three daily dosages (morning-midday-evening), for seven consecutive days.
Exercise Biochemistry Laboratory, School of Physical Education & Sports Sciences, University of Thessaly
Trikala, Greece
Change in total antioxidant capacity in serum
Time frame: At baseline and daily throughout the study, up to 11 days
Change in protein carbonyls in serum
Time frame: At baseline and daily throughout the study, up to 11 days
Change in thiobarbituric acid reactive substances in serum
Time frame: At baseline and daily throughout the study, up to 11 days
Change in reduced glutathione in red blood cells
Time frame: At baseline and daily throughout the study, up to 11 days
Change in oxidized glutathione in red blood cells
Time frame: At baseline and daily throughout the study, up to 11 days
Change in creatine kinase in activity in plasma
Time frame: At baseline and daily throughout the study, up to 11 days
Change in white blood cell count in blood
Time frame: At baseline and daily throughout the study, up to 11 days
Change in repeated sprint ability
Players' repeated sprint ability was assessed via a repeared sprint test. Each player performed 5 x 30 meters sprints interspersed by 25 seconds of active recovery. Sprint time was recorded by using infrared photoelectrical gates.
Time frame: At baseline and daily throughout the study, up to 11 days
Change in high intensity running during the game
High intensity running (i.e. \> 14km/h) during the games was monitored by utilizing high time-resolution GPS devices.
Time frame: During games 1, 2 and 3
Change in blood lactate concentration during the game
Time frame: During games 1, 2 and 3
Change in average heart rate during the game
Time frame: During games 1, 2 and 3
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.