Antioxidant Status, Exercise-induced Aseptic Inflammation, Skeletal Muscle Damage, Skeletal Muscle Performance
Conditions
Brief summary
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.
Detailed description
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.
Interventions
DIETARY_SUPPLEMENTN-acetylcysteine
Orally in three daily dosages (morning-midday-evening), at 20 mg/kg/day, for seven consecutive days.
DIETARY_SUPPLEMENTPlacebo
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.
Sponsors
University of Thessaly
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
MALE
Age
18 Years to 28 Years
Healthy volunteers
Yes
Inclusion criteria
* Participation at elite level (top three division leagues) of soccer competition for at least five years * Abstained from consumption of performance-enhancing supplements, antioxidant supplements and medications (for at least 6 months before and during the study) * Participation in at least six two-hour training sessions and one match per week * Non-smokers
Exclusion criteria
* A known NAC intolerance or allergy * A recent febrile illness * History of muscle lesion * Lower limb trauma * Metabolic diseases
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in oxidized glutathione in red blood cells | At baseline and daily throughout the study, up to 11 days | — |
| Change in creatine kinase in activity in plasma | At baseline and daily throughout the study, up to 11 days | — |
| Change in total antioxidant capacity in serum | At baseline and daily throughout the study, up to 11 days | — |
| Change in reduced glutathione in red blood cells | At baseline and daily throughout the study, up to 11 days | — |
| Change in protein carbonyls in serum | At baseline and daily throughout the study, up to 11 days | — |
| Change in thiobarbituric acid reactive substances in serum | At baseline and daily throughout the study, up to 11 days | — |
| Change in white blood cell count in blood | At baseline and daily throughout the study, up to 11 days | — |
| Change in repeated sprint ability | At baseline and daily throughout the study, up to 11 days | 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. |
| Change in high intensity running during the game | During games 1, 2 and 3 | High intensity running (i.e. \> 14km/h) during the games was monitored by utilizing high time-resolution GPS devices. |
Secondary
| Measure | Time frame |
|---|---|
| Change in blood lactate concentration during the game | During games 1, 2 and 3 |
| Change in average heart rate during the game | During games 1, 2 and 3 |
Countries
Greece
Outcome results
None listed