Ionized Magnesium in Athletes

Ionized Magnesium Concentration in Athletes and Exercise Induced Changes in Ionized Magnesium

Ionized magnesium variation is measured during a normal day and again during a day with an exercise protocol of 90 minutes.

Study Overview

• Status: Unknown
• Conditions: Magnesium Deficiency
• Intervention / Treatment: Behavioral: Exercise protocol

Detailed Description

Magnesium is an essential micronutrient for health and exercise performance. Deficiencies are common, especially in case of insufficient diets. Athletes are a population at risk of magnesium deficiency, as they can have strong nutritional (dis)believes and increased losses through sweat. That is why monitoring magnesium status in athletes is very important. Ionized magnesium is the active form of total magnesium, this value might be even more important than total magnesium. However, whether ionized magnesium is influenced by day variation is not clear yet. In addition: one bout of exercise can change magnesium status and probably ionized magnesium status. For people active in sports it is important to be aware of this variation in magnesium status, to prevent the diagnosis of false inadequate magnesium status. Therefore it is the aim of this proposal to determine whether ionized magnesium varies within one day and whether it changes after an acute bout of exercise.

Objective:

The main objective is to investigate whether ionized magnesium concentration varies during one day, and whether it is changed after one bout of exercise

Study design:

This will be a cross-over design. With screening and preliminary tests before the exercise test day and the non-exercise test day. The order in which exercise day and non-exercise day will be done, will be randomly divided between the participants.

Intervention:

A rest day and an exercise day At exercise day: an exercise test of 90 min at 70% of VO2max. Blood samples are taken at set time points during rest day and exercise day

• Study Type: Interventional
• Enrollment (Actual): 18
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 43 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age: 18 - 45 y
• BMI: 18.5 - 25
• Minimal of 5 hours of training per week, for at least 2 years
• Used to bike, at least 5 hours per week in high season
• No Mg and / or Ca supplementation during study
• No blood donation, during or in the 6 weeks preliminary the study
• Suitable veins
• No chronic medication, with the exception of paracetamol and or birth control
• No antibiotics in the month preliminary the study
• Good health
• Serum Mg > 0.7 mmol/L
• Willing to give blood
• Able to be present and participate at all test days

Exclusion Criteria:

• Chronical illness
• Use of medication with the exception of paracetamol and or birth control
• Mg and or Ca supplementation use
• Inadequate Mg intake (according to FFQ)
• Working at Human Nutrition
• Wageningen University Msc thesis or internship at Human Nutrition
• Participating in other scientific research (with the exception of EetMeetWeet)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Exercise day; Behavioral intervention: 90min bike ergometer test at 70% of VO2max. Blood samples are collected at set time points (08:30, 11:00, 12:30, 13:30, 15:00, 16:00 and 18:30). Blood samples are analyzed on the pHOx analyzer for their ionized magnesium concentration. And on the Dimension Vista 1500 from Siemens for their total magnesium concentration.	Behavioral: Exercise protocol; 70% VO2max bike ergometer test for 90 minutes
No Intervention: Non exercise day (Rest day); No exercise protocol. Estimating daily variation of magnesium concentration. Blood samples are collected at set time points (08:30, 11:00, 12:30, 13:30, 15:00, 16:00 and 18:30). Blood samples are analyzed on the pHOx analyzer for their ionized magnesium concentration. And on the Dimension Vista 1500 from Siemens for their total magnesium concentration.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood samples analyzed on the pHOx analyzer for their ionized magnesium concentration	blood	Blood samples are collected at 7 set time points during one day

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
blood samples are analyzed on the Dimension Vista 1500 of Siemens for their total magnesium concentration	blood plasma	Blood samples are collected at 7 set time points during one day

Collaborators and Investigators

• Sponsor: Wageningen University
• Collaborators: Gelderse Vallei Hospital
• Investigators: Principal Investigator: Jacqueline Klein Gunnewiek, Phd, Gelderse Vallei Hospital

Study record dates

Study Major Dates

• Study Start: December 1, 2015
• Primary Completion (Anticipated): March 1, 2016
• Study Completion (Anticipated): March 1, 2016

Study Registration Dates

• First Submitted: December 9, 2015
• First Submitted That Met QC Criteria: February 1, 2016
• First Posted (Estimate): February 4, 2016

Study Record Updates

• Last Update Posted (Estimate): February 4, 2016
• Last Update Submitted That Met QC Criteria: February 1, 2016
• Last Verified: February 1, 2016

More Information

Terms related to this study

• Keywords: Exercise; Blood; Athletes; Variation; Ionized Magnesium
• Additional Relevant MeSH Terms: Nutrition Disorders; Deficiency Diseases; Malnutrition; Magnesium Deficiency
• Other Study ID Numbers: NL54333.081.15

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Yes
• IPD Plan Description: Participants receive a letter with their personal information. VO2max, body weight and height, total Magnesium and ionized magnesium will be communicated.