Clinical trial NCT02621320: Vitamin D Supplementation in Wheelchair Indoor Athletes
Official title: Effect of Vitamin D3 Supplementation on Exercise Performance in Wheelchair Athletes.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Vitamin D Deficiency
Spinal Cord Injury
Drug Effects
Dietary Supplements
Physical Education and Training/Methods
Keywords: Vitamin D
Exercise Performance
Wheelchair Athletes
Indoor sports
Wingate
Isokinetic Dynamometer
Lead sponsor: Swiss Paraplegic Research, Nottwil
Sponsor class: NETWORK
First posted: 2015-12-03
Enrollment: 20
Sex: MALE
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: There is a high prevalence of vitamin D deficiency in Switzerland. In indoor-athletes as well as wheelchair users, vitamin D deficiency occurs even more often. It is well established that vitamin D deficiency has a negative effect on health. However, vitamin D supplementation in individuals with a vitamin D deficiency has a positive effect on muscle performance. In recently published studies with able-bodied subjects, it has been shown that a normal vitamin D level (\>75nmol/L) can only be achieved with a high-dose supplementation of vitamin D.

The aim of this study is to examine the effect of vitamin D supplementation on exercise performance in wheelchair athletes with vitamin D deficiency . All participants with a vitamin D deficiency are assigned to the intervention group and treated with 6000 IU of vitamin D3 daily over a period of 12 weeks. All participants who have a normal vitamin D level will receive placebo treatment (control group). The physical performance is measured three times at baseline, after six weeks and 12 weeks. The measurements include a Wingate and a dynamometer test.


Eligibility criteria: Inclusion Criteria:

* swiss elite wheelchair athlete
* 18 to 60 years
* male, healthy
* at least 2x45min sports a week

Exclusion Criteria:

* participation in another study
* medication which influences performance
* respiratory and cardiovascular disease
* daily intake of \>400IU Vitamin D
* parathyroid gland disease
* kidney insufficiency
* visit abroad below the 37th parallel latitude during study or shortly before

Primary outcomes:
measure: peak power
timeFrame: delta change from pre to 12 weeks post supplementation
measure: maximum torque
timeFrame: delta change from pre to 12 weeks post supplementation
Secondary outcomes:
measure: Vitamin D serum level
timeFrame: week 0, 1 day before they start supplementation
measure: Vitamin D serum level
timeFrame: 12 weeks post supplementation
measure: Count of injuries
timeFrame: 12 weeks post supplementation
Other outcomes:
measure: Heart rate
timeFrame: week 0, 1 day before they start supplementation
measure: Heart rate
timeFrame: 12 weeks post supplementation
measure: blood lactate concentration
timeFrame: week 0, 1 day before they start supplementation
measure: blood lactate concentration
timeFrame: 12 weeks post supplementation
Locations:
city: Nottwil
country: Switzerland
facility: Swiss Paraplegic Centre
state: Lucerne
Study officials:
References: