UCLA Magnesium Formulation Athlete Study (Mg-Form)

Effects of Magnesium Glycinate and Magnesium L-Threonate on Sleep, Recovery, and Performance in Collegiate Athletes

This randomized, double-blind, placebo-controlled trial will compare magnesium glycinate, magnesium L-threonate, and placebo in UCLA varsity athletes. Participants will complete a baseline monitoring period followed by 4 weeks of blinded nightly supplementation. WHOOP or study-approved wearable data will be used to evaluate sleep efficiency, total sleep time, sleep consistency, heart rate variability, resting heart rate, and recovery metrics. Baseline and final testing will assess selected reaction and physical performance outcomes. The primary outcome is change in WHOOP-derived sleep efficiency from baseline week to final treatment week.

Study Overview

• Status: Not yet recruiting
• Conditions: Sleep; Recovery; Athletic Performance
• Intervention / Treatment: Dietary supplement: Magnesium glycinate; Dietary supplement: Magnesium L-threonate; Other: Placebo

Detailed Description

Magnesium is involved in neuromuscular signaling, cellular energy metabolism, autonomic regulation, and sleep-related physiology. Competitive athletes often experience sleep restriction, training stress, travel, soreness, and recovery demands. Magnesium glycinate and magnesium L-threonate are commonly used athlete-facing magnesium formulations, but they are not interchangeable. Glycinate is commonly positioned as a well-tolerated sleep-oriented formulation, whereas L-threonate is of interest because of prior signals related to sleep, cognition, reaction performance, and central nervous system magnesium biology. This single-site UCLA study will enroll adult varsity athletes aged 18 to 35 years. Participants will complete screening, informed consent, baseline assessments, wearable monitoring, a baseline monitoring period, randomization in a 1:1:1 ratio, 4 weeks of blinded nightly capsules, brief daily REDCap morning surveys, weekly adherence and safety check-ins, and final performance-adjacent testing. The primary outcome is change in average WHOOP-derived sleep efficiency from baseline week to final treatment week. Prespecified primary contrasts will compare magnesium glycinate versus placebo and magnesium L-threonate versus placebo. Total sleep time, sleep consistency, resting heart rate, heart rate variability, WHOOP Recovery Score, reaction-time performance, grip strength, countermovement jump height, adherence, tolerability, and adverse events will be analyzed as secondary or exploratory outcomes according to the final statistical analysis plan. The magnesium glycinate versus magnesium L-threonate contrast will be treated as exploratory unless the final statistical analysis plan preserves alpha for that comparison.

• Study Type: Interventional
• Enrollment (Estimated): 150
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jeremy Swisher, MD; Phone Number: 936-520-3595; Email: jswisher@mednet.ucla.edu
• Study Contact Backup: Name: Kimberly Burbank, MD; Email: kburbank@mednet.ucla.edu

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90095
      • University of California, Los Angeles
      • Contact: Jeremy Swisher, MD; Phone Number: 936-520-3595; Email: jswisher@mednet.ucla.edu
      • Contact: Kimberly Burbank, MD; Email: kburbank@mednet.ucla.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Age 18 to 35 years.
• Current UCLA varsity athlete.
• Actively training or competing during the study period.
• Willing to wear WHOOP or a study-approved wearable device continuously during baseline and treatment periods if wearable data are used.
• Willing to take assigned study capsules nightly for 28 days.
• Willing to complete brief daily REDCap surveys and weekly adherence/safety check-ins.
• Able to provide informed consent and comply with study procedures.

Exclusion Criteria:

• Current magnesium supplementation without completion of an appropriate washout before baseline.
• Current investigational drug or investigational supplement use.
• Current use of prescription or over-the-counter sleep medications unless reviewed and permitted by the study clinician.
• Diagnosed sleep disorder that, in the investigator's judgment, would confound outcomes or increase risk.
• Significant kidney disease or another medical condition that may increase risk with magnesium supplementation.
• Known intolerance or allergy to magnesium glycinate, magnesium L-threonate, placebo, or inactive study ingredients.
• Use of medications with clinically relevant magnesium interactions unless reviewed and permitted by the study clinician.
• Any other condition that, in the investigator's judgment, would make participation unsafe, compromise voluntary consent, or prevent valid outcome assessment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Magnesium Glycinate; Participants randomized to this arm will take blinded magnesium glycinate capsules nightly for 4 weeks. The current planning dose is approximately 240 mg elemental magnesium nightly, with final capsule count and label language based on the selected blinded formulation.	Dietary supplement: Magnesium glycinate; Blinded oral magnesium glycinate capsules taken nightly for 28 days.
Experimental: Magnesium L-Threonate; Participants randomized to this arm will take blinded magnesium L-threonate capsules nightly for 4 weeks. The current planning target is approximately 2 g/day total magnesium L-threonate, with elemental magnesium content, capsule count, and label language confirmed before activation.	Dietary supplement: Magnesium L-threonate; Blinded oral magnesium L-threonate capsules taken nightly for 28 days.
Placebo Comparator: Placebo; Participants randomized to this arm will take matching placebo capsules nightly for 4 weeks on the same blinded schedule.	Other: Placebo; Matching placebo capsules taken nightly for 28 days.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in WHOOP-derived sleep efficiency percentage from baseline week to final treatment week	Average nightly WHOOP-derived sleep efficiency, expressed as a percentage, will be calculated for the baseline week and final treatment week. A valid week requires at least 5 usable nights in the 7-day window. The outcome is final-treatment-week average minus baseline-week average; higher values indicate improved sleep efficiency.	Baseline week to final treatment week, approximately 5 weeks total including baseline monitoring

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in BlazePod RIW Challenge reaction time in milliseconds from baseline to final visit	Reaction performance will be measured using the prespecified BlazePod RIW Challenge protocol. The outcome is change in reaction time in milliseconds from baseline to final visit. Lower reaction time indicates better performance.	Baseline to final visit, approximately 5 weeks
Change in BlazePod Speed Tap reaction time in milliseconds from baseline to final visit	Reaction performance will be measured using the prespecified BlazePod Speed Tap protocol. The outcome is change in reaction time in milliseconds from baseline to final visit. Lower reaction time indicates better performance.	Baseline to final visit, approximately 5 weeks
Change in WHOOP-derived sleep consistency score from baseline week to final treatment week	WHOOP-derived sleep consistency score, or an equivalent prespecified wearable-derived sleep timing regularity metric, will be summarized for the baseline week and final treatment week. The outcome is final-treatment-week average minus baseline-week average.	Baseline week to final treatment week, approximately 5 weeks total including baseline monitoring
Change in WHOOP-derived total sleep time in minutes from baseline week to final treatment week	Average nightly total sleep time captured by WHOOP, expressed in minutes, will be calculated for the baseline week and final treatment week. The outcome is final-treatment-week average minus baseline-week average.	Baseline week to final treatment week, approximately 5 weeks total including baseline monitoring
Change in WHOOP-derived resting heart rate in beats per minute from baseline week to final treatment week	Nightly resting heart rate captured by WHOOP, expressed in beats per minute, will be summarized as weekly averages for the baseline week and final treatment week. The outcome is final-treatment-week average minus baseline-week average.	Baseline week to final treatment week, approximately 5 weeks total including baseline monitoring
Change in WHOOP-derived heart rate variability in milliseconds from baseline week to final treatment week	Nightly heart rate variability captured by WHOOP, expressed in milliseconds, will be summarized as weekly averages for the baseline week and final treatment week. The outcome is final-treatment-week average minus baseline-week average.	Baseline week to final treatment week, approximately 5 weeks total including baseline monitoring
Change in WHOOP Recovery Score from baseline week to final treatment week	WHOOP Recovery Score, reported on a 0 to 100 scale where higher scores indicate better recovery, will be summarized as weekly averages for the baseline week and final treatment week. The outcome is final-treatment-week average minus baseline-week average.	Baseline week to final treatment week, approximately 5 weeks total including baseline monitoring
Change in VALD dynamometer bilateral average handgrip strength from baseline to final visit	Bilateral average handgrip strength will be measured with the prespecified VALD handgrip dynamometer protocol. The outcome is final-visit bilateral average handgrip strength minus baseline bilateral average handgrip strength.	Baseline to final visit, approximately 5 weeks
Change in VALD force plate countermovement jump height from baseline to final visit	Countermovement jump height will be measured with the prespecified VALD force plate protocol. The outcome is final-visit jump height minus baseline jump height.	Baseline to final visit, approximately 5 weeks
Number of participants with adverse events and supplement tolerability concerns	The number of participants with adverse events, tolerability concerns, dose interruptions, and study-product discontinuations will be summarized by study arm. Events of interest include gastrointestinal symptoms, sedation, dizziness, headache, allergic reaction, skin irritation from wearable use, and study-product discontinuation.	From first dose through final visit, approximately 4 weeks

Collaborators and Investigators

• Sponsor: University of California, Los Angeles
• Investigators: Principal Investigator: Jeremy Swisher, MD, University of California, Los Angeles; Study Director: Joshua Goldman, MD, University of California, Los Angeles

Publications and helpful links

General Publications

• Walsh NP, Halson SL, Sargent C, Roach GD, Nedelec M, Gupta L, Leeder J, Fullagar HH, Coutts AJ, Edwards BJ, Pullinger SA, Robertson CM, Burniston JG, Lastella M, Le Meur Y, Hausswirth C, Bender AM, Grandner MA, Samuels CH. Sleep and the athlete: narrative review and 2021 expert consensus recommendations. Br J Sports Med. 2020 Nov 3:bjsports-2020-102025. doi: 10.1136/bjsports-2020-102025. Online ahead of print.
• Hausenblas HA, Lynch T, Hooper S, Shrestha A, Rosendale D, Gu J. Magnesium-L-threonate improves sleep quality and daytime functioning in adults with self-reported sleep problems: A randomized controlled trial. Sleep Med X. 2024 Aug 17;8:100121. doi: 10.1016/j.sleepx.2024.100121. eCollection 2024 Dec 15.
• Schuster J, Cycelskij I, Lopresti A, Hahn A. Magnesium Bisglycinate Supplementation in Healthy Adults Reporting Poor Sleep: A Randomized, Placebo-Controlled Trial. Nat Sci Sleep. 2025 Aug 30;17:2027-2040. doi: 10.2147/NSS.S524348. eCollection 2025.
• Mah J, Pitre T. Oral magnesium supplementation for insomnia in older adults: a Systematic Review & Meta-Analysis. BMC Complement Med Ther. 2021 Apr 17;21(1):125. doi: 10.1186/s12906-021-03297-z.
• Miller DJ, Lastella M, Scanlan AT, Bellenger C, Halson SL, Roach GD, Sargent C. A validation study of the WHOOP strap against polysomnography to assess sleep. J Sports Sci. 2020 Nov;38(22):2631-2636. doi: 10.1080/02640414.2020.1797448. Epub 2020 Jul 26.
• Gupta L, Morgan K, Gilchrist S. Does Elite Sport Degrade Sleep Quality? A Systematic Review. Sports Med. 2017 Jul;47(7):1317-1333. doi: 10.1007/s40279-016-0650-6.

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: May 26, 2026
• First Submitted That Met QC Criteria: June 5, 2026
• First Posted (Actual): June 11, 2026

Study Record Updates

• Last Update Posted (Actual): June 11, 2026
• Last Update Submitted That Met QC Criteria: June 5, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: collegiate athletes; dietary supplement; heart rate variability; reaction time; sleep duration; placebo-controlled trial; WHOOP; magnesium glycinate; magnesium L-threonate; athlete recovery
• Additional Relevant MeSH Terms: threonic acid; magnesium diglycinate
• Other Study ID Numbers: IRB-26-1185

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: No individual participant data sharing is planned because the study involves a relatively small cohort of collegiate athletes and individual-level sleep, recovery, performance, and sport-related data may create re-identification risk. Aggregate results may be disseminated through presentations, manuscripts, and ClinicalTrials.gov summaries as applicable.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No