Summary
Participants are being invited to take part in a research study. Before deciding whether to take part, it is important for participants to understand why the research is being done and what it will involve.
Purpose: This study will investigate whether a multi-ingredient nutritional supplement containing magnesium and melatonin can improve sleep quality in adults who experience disrupted sleep due to nighttime leg cramps.
What participation involves: Participation lasts 8 weeks. Participants will be randomly assigned to take either the nutritional supplement or a placebo (inactive look-alike) every night before bed for 6 weeks. Participants will wear an Oura Ring wearable device on one finger continuously for 8 weeks throughout the study and complete short questionnaires using a smartphone app. The Oura Ring and study supplement will be sent to the participant's home address. Participants will never need to travel to a research centre; all contact with the research team will be by video call, phone, messaging, or email.
How long: Total involvement will be 8 weeks, made up of a 2-week baseline period and a 6-week supplementation period. Each day, participants will complete a short app-based questionnaire (approximately 1 minute). At the end of weeks 2, 4, 6, and 8, participants will complete additional app-based questionnaires (approximately 10 minutes).
Eligibility Criteria
Age Range: 40 years to 75 years
Inclusion Criteria:
* Adults aged 40-75 years
* Self-reported poor sleep quality (PSQI \>5) at screening
* Self-reported nocturnal leg cramp averaging ≥4 episodes per fortnight at screening
* Capacity to understand and provide electronic informed consent
* Willing to wear an Oura Ring wearable device continuously throughout the study period
* Access to a smartphone/tablet with iOS 15 or higher and Android 9 or higher and willing to install and use the Oura and Trialflare applications
* Be a resident of and permanently living in Florida with no planned travel across more than one time zone for at least 1 night during the study period
Exclusion Criteria:
* Current or recent (within 4 weeks of randomisation) use of melatonin, magnesium, or other supplements specifically taken for sleep or leg cramps or listed as an ingredient of the intervention supplement.
* Current use of any prescription medication
* Diagnosed sleep disorder (e.g. obstructive sleep apnoea, restless legs syndrome, insomnia disorder)
* Known or suspected secondary cause of nocturnal leg cramps (e.g. peripheral vascular disease, neurological condition, renal impairment, thyroid disorder)
* Any current or prior diagnosis of:
* Cancer or malignancy of any kind (prior malignancy is not exclusionary if the participant is in confirmed remission and has completed all treatment)
* Cardiovascular disease (e.g. hypertension, coronary artery disease, heart failure, arrhythmia, stroke, peripheral vascular disease)
* Autoimmune disorder (e.g. rheumatoid arthritis, lupus, multiple sclerosis)
* Gastrointestinal disorder (e.g. IBS, malabsorption syndromes)
* Neurological disorder (e.g. epilepsy, Parkinson's disease, dementia)
* Hepatic or renal impairment
* Diabetes mellitus (type 1 or type 2)
* Severe psychiatric disorder (e.g. schizophrenia, bipolar disorder)
* Myasthenia Gravis
* Known hypersensitivity or allergy to any ingredient in the active or placebo product
* Rotating shift work or irregular sleep patterns
* Current participation in another interventional clinical trial
* Inability to comply with study procedures or remote visit schedule
* Breastfeeding, pregnant, or planning to become pregnant during the study period