S-Acetyl Glutathione and Performance Recovery in Soccer

What Was Tested

The trial (not phased) is built around Glutathione.

However, in modern soccer, players participate very often in 2 or 3 matches within a week, with a recovery period of 72 hours between successive matches, that is insufficient to restore skeletal muscle homeostasis and performance.

It had three arms (groups): SAG-200 Trial (experimental), SAG-500 Trial (experimental) and Placebo Trial (placebo comparator).

Oral administration of S-Acetyl Glutathione (SAG).

Oral administration of S-Acetyl Glutathione (SAG).

Oral administration of placebo.

The registry classes the interventions as dietary supplement.

More on the Plan

The duration of each trial will be 11 days, including a 7-day pre-loading period (days 1 -7), a match day (day 8) and 3 consecutive recovery days after the match (days 9-11).

Between trials a 3-week washout period will be implemented.

Pre-loading period: During the 7-day pre-loading period players will participate daily in training sessions according to a soccer-specific weekly training schedule, while receiving the respective supplement.

Blood samples will be collected on day 1 and day 7 while daily nutrient intake (via 7-day diet recalls), physical activity level (via accelerometry) and training load (via global positioning system instrumentation during training sessions) will be monitored daily.

Who Took Part

Enrollment: 20 planned participants were the target.

It was open to people of any sex aged from 19 years up to 29 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Participation at elite (top three division leagues) for ≥ 4 years. No recent history of febrile illness, musculoskeletal problems and metabolic diseases. No consumption of medications and performance-enhancing supplements (including anti-inflammatory, antioxidants, vitamins and multivitamin supplements) for at least 6 months prior to the study. Participation in at least 5 training sessions and 1 match per week.

The full record lists 5 inclusion and 4 exclusion criteria; among the exclusions: musculoskeletal injury; consumption of medication and performance-enhancing supplements; illness during the course of the study.

How the Study Was Run

The set-up was randomized, crossover and triple-blind.

Because people in this Glutathione study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

In the crossover set-up each of the participants took both Glutathione and the comparison in turn, acting as their own control.

Blinding on both sides kept the participants and researchers unaware of who received Glutathione.

Those kept unaware of assignments: participant, investigator and outcomes assessor.

It started in 2026-09-01 with completion listed for 2026-12-20.

It ran at 1 site in Greece.

Its stated primary purpose is other.

What Was Measured

Researchers chose this as the main measure: Change in creatine kinase levels (time frame: Day 1, day 7, day 9, day 10 and day 11). Change in myoglobin levels (time frame: Day 1, day 7, day 9, day 10 and day 11). Change in oxidized glutathione (time frame: Day 1, day 7, day 9, day 10 and day 11).

It also tracked 10 secondary outcomes, for example Change in total distance covered, Change in internal load, Change in dietary intake, Change in time spent in moderate-to-vigorous physical activity, Change in distance covered with high-intensity running and Change in distance covered with sprinting.

What This Means in Plain Language

Put simply, this is a not phased, randomized trial of Glutathione in 20 people.

Its size is small, so on its own it can only give an early look.

Its status is not yet recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Glutathione compound page, all human trials.