Effects of Vitamin D on Skeletal Muscle Strength in Resistance Trained Adult Females

Sponsor

Auburn University (Other)

Overall Status

Not yet recruiting

CT.gov ID

NCT05489666

Collaborator

(none)

Enrollment

Arms

Anticipated Duration (Months)

Study Details

Study Description

Brief Summary

The majority of vitamin D research has been done in non-athletic populations, particularly older populations, to analyze muscle weakness, pain, balance, and fractures. It has been reported that over a billion people worldwide are vitamin D deficient, including 36-70% of the young adult population. Previous literature also suggests that, even among healthy athletes, over 50% of subjects sampled had inadequate or insufficient vitamin D levels. Vitamin D deficiency can occur in young women, including pregnant women, and the risk of deficiency is even higher with advancing age in a woman's lifecycle. It is known that preserving skeletal muscle (SM) function is critical for women of all ages to prevent sarcopenia. Two factors in preserving SM are protein intake and resistance training. Relatively unknown are the actions of Vitamin D on SM function. Vitamin D deficiency can have a negative effect on SM function . However, additional research is needed to investigate the increase in SM strength when the serum concentration of vitamin D is improved. It is possible that an athlete may require an increased intake of vitamin D to assure adequate availability and storage for optimal performance; however, is known that food sources of vitamin D are limited in sufficient quantity to meet these requirements. Athletes who are insufficient will require a supplement of vitamin D3 for up to 5000 IU/day for at least eight weeks, to potentially reach optimal levels, then 1000-2000 IU/day for maintenance.

Condition or Disease	Intervention/Treatment	Phase
Nutrition Status Nutritional Requirements Sports Nutritional Sciences	Dietary Supplement: Nature Made Vitamin D3 5,000 IU, 125mcg Dietary Supplement: Placebo	N/A

Detailed Description

The investigators seek to determine if women with a vitamin D serum concentration lower than 50 nmol/L and who regularly resistance train will improve strength performance outcomes when taking a daily supplement of 5000 IU of vitamin D3 over an 8-week period, as compared to the same demographic of women who do not take a daily supplement of vitamin D3. The participants will receive "Nature's Bounty Vitamin D3, 5,000 IU, soft gels" and the PI will be providing the supplement and the placebo. A pre-intervention data collection and screening (PRE) will be performed involving blood draw, food log, a body composition test (using Dual-energy X-ray absorptiometry [DEXA]), and a BioDex testing to determine maximal muscle strength. Following PRE testing, the participants will be divided into one of two groups: 1) taking a vitamin D3 supplement (n=20) or, 2) taking a placebo. The participants will be instructed to continue their resistance training regimen. Training will be logged and turned in to the PI weekly. The participants will perform a post-intervention data collection (POST), which includes the same test from PRE. Variables of interest will include changes in: 1) blood level of vitamin D, 2) muscle and fat mass, and 3) leg strength/power during the BioDex test.

Study Design

Study Type:

Interventional

Anticipated Enrollment :

40 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Intervention Model Description:

A two-arm parallel assignment; one group receives the treatment (vitamin D3 supplement 5,000IU/day) and one group receives the placebo (control).A two-arm parallel assignment; one group receives the treatment (vitamin D3 supplement 5,000IU/day) and one group receives the placebo (control).

Masking:

Double (Participant, Investigator)

Masking Description:

Double-blind masking; neither the investigator nor the participants will know, the assigned intervention placement.

Primary Purpose:

Basic Science

Official Title:

Effects of Vitamin D on Skeletal Muscle Strength in Resistance Trained Adult Females

Anticipated Study Start Date :

Sep 1, 2022

Anticipated Primary Completion Date :

Nov 30, 2022

Anticipated Study Completion Date :

Feb 1, 2023

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: Treatment Group Participants in this group will be administered an oral Vitamin D3 supplement; 5,000 IU/ day. The participants will take the supplement themselves, orally, once per day, for 8 weeks.	Dietary Supplement: Nature Made Vitamin D3 5,000 IU, 125mcg Taking a 5,000 IU oral supplement of Vitamin D3, daily, for 8 weeks, may improve strength performance in women who have and are continuing a resistance trained workout regimen. After blood vitamin D levels have been raised to an optimal range, a lower dosage may be assigned as needed from 5,000 IU per day to 1,000-2,000 IU per day. Other Names: Spring Valley Life Extensions GNC Nature's Bounty CVSHealth Swanson
Placebo Comparator: Control Group Participants in this group will be administered an oral, soft-gel, lookalike placebo. The participants will take the supplement themselves, orally, once per day, for 8 weeks.	Dietary Supplement: Placebo Resistance trained women may not improve their strength performance with low levels of vitamin D in the blood.

Arm

Intervention/Treatment

Active Comparator: Treatment Group

Participants in this group will be administered an oral Vitamin D3 supplement; 5,000 IU/ day. The participants will take the supplement themselves, orally, once per day, for 8 weeks.

Dietary Supplement: Nature Made Vitamin D3 5,000 IU, 125mcg

Taking a 5,000 IU oral supplement of Vitamin D3, daily, for 8 weeks, may improve strength performance in women who have and are continuing a resistance trained workout regimen. After blood vitamin D levels have been raised to an optimal range, a lower dosage may be assigned as needed from 5,000 IU per day to 1,000-2,000 IU per day.

Other Names:

Spring Valley

Life Extensions

GNC

Nature's Bounty

CVSHealth

Swanson

Placebo Comparator: Control Group

Participants in this group will be administered an oral, soft-gel, lookalike placebo. The participants will take the supplement themselves, orally, once per day, for 8 weeks.

Dietary Supplement: Placebo

Resistance trained women may not improve their strength performance with low levels of vitamin D in the blood.

Outcome Measures

Primary Outcome Measures

Biodex Strength performance change [8 weeks]
Taking a daily supplement of 5,000 IU of vitamin D3 may change strength outcomes measured in newton meters (Nm).

Secondary Outcome Measures

Serum 25(OH)D status [8 weeks]
Taking a daily supplement of 5,000 IU of vitamin D3 may change blood levels of vitamin D.

Eligibility Criteria

Criteria

Ages Eligible for Study:

19 Years to 55 Years

Sexes Eligible for Study:

Female

Accepts Healthy Volunteers:

Yes

Inclusion criteria will include:

Participant will need to answer "yes" to the following items:

female
not pregnant
between the ages of 19-55 years old
a non-smoker
currently resistance training (i.e., lifting weights) for more than 2 days/week for a minimum of > 24 months
free of any known overt cardiovascular or metabolic disease
not an active user of tanning beds
not consuming now or haven't consumed within the last 6 months, a vitamin D or multivitamin supplement or a form of a supplement with vitamin D added
not consuming now or haven't consumed within the last 2 months, agents that affect hormones (testosterone boosters, growth hormone boosters, etc.) (does not include birth control/oral contraceptives)
not allergic to rubbing alcohol