Elite soccer players with higher vitamin D can change direction quickly – June 2024

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The Relationships of Serum Vitamin D Concentration with Linear Speed and Change of Direction (COD) Performance in Soccer Players (preprint)

doi: 10.20944/preprints202406.0521.v1
Michalczyk M.M *, Roczniok R and Golas A 2
Department of Sports Nutrition, The Jerzy Kukuczka Academy of Physical Education in Katowice, 40-065 Katowice, Poland
Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education in Katowice, 40-065 Katowice, Poland
* Correspondence: m.michalczyk at awf.katowice.pl

The aim of the study was to establish whether the level of 25 hydroxyvitamin D (25(OH)D) in serum has an influence on speed (s) and change of direction (COD, s) performance. Twenty male soccer players from the top league participated in the study. All subjects were evaluated for the serum concentration of 25(OH)D at the beginning of the preseason. The linear sprint test was performed at 5m and 30m, and COD (time and deficit) at the beginning (BPP) and after (APP) 6 weeks of the preparatory period. The results revealed that 20% of soccer players had a significant deficiency of 25(OH)D (<20 ng/ml) and 30% had insufficient 25(OH)D levels (between 20-30 ng/ml). Positive correlations were found between the training effect for the ACOD (BPP - APP) (p=0.003) and Adeficit (BPP-APP) (p=0.039).
Significant differences were noticed for the ACOD (m=0.60 [s]) and Adeficit (m=0.56s) in the soccer players whose 25(OH)D concentration was <=30 ng/ml, and for the ACOD (p=0.002) and Adeficit (p=0.017) in the soccer players whose 25(OH)D concentration was >30 ng/ml. The training effect was significantly higher for the soccer players whose 25(OH)D concentration was above 30 ng/ml. Soccer players whose serum 25(OH)D concentrations were >30 ng/ml achieved better results in the applied tests.
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VitaminDWiki – Overview Sports and vitamin D contains

Athletes are helped by vitamin D by:

1. Faster reaction time
2. Far fewer colds/flus during the winter
3. Less sore/tired after a workout
4. Fewer micro-cracks and broken bones
5. Bones which do break heal much more quickly
6. Increased VO2 and exercise endurance Feb 2011
7. Indoor athletes especially need vitamin D
8. Professional indoor athletes are starting to take vitamin D and/or use UV beds
9. Olympic athletes have used UV/vitamin D since the 1930's
10. The biggest gain from the use of vitamin D is by those who exercise less than 2 hours per day.
11. Reduced muscle fatigue with 10,000 IU vitamin D daily
12. Muscle strength improved when vitamin D added: 3 Meta-analysis
13. Reduced Concussions
    See also: Sports and Vitamin D category 274 items

1. reason listed above shows more force/faster reation time if higher level of vitamin D (helps prevent falls)

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Do fast twitch muscles respond more quickly if there is a higher level of vitamin D in the blood?

Asked Perplexity AI June 2024 click to see 5 references
Yes, higher levels of vitamin D in the blood are associated with improved function and development of fast-twitch (type II) muscle fibers, which are responsible for quick, powerful movements.
Vitamin D appears to have a specific effect on fast-twitch muscle fibers in several ways:

1. It induces hypertrophy (growth) of type II muscle fibers, increasing their size and number.
2. It enhances the differentiation and development of type II muscle fiber cells.
3. Vitamin D deficiency leads to preferential atrophy (wasting) of type II muscle fibers over slow-twitch fibers.
4. Supplementing with vitamin D increases the percentage and cross-sectional area of type II muscle fibers.
5. Higher vitamin D levels are associated with improved muscle power, force, velocity and performance in activities requiring fast-twitch fibers like jumping.
6. Vitamin D supplementation in deficient individuals improves muscle strength and athletic performance measures that rely heavily on fast-twitch fibers, such as sprint speed and vertical jump.

So in summary, maintaining adequate vitamin D levels appears crucial for optimizing the size, function and recruitment of the fast-twitch muscle fibers that allow for rapid, powerful contractions during athletic activities. Deficiency can lead to preferential atrophy of these fibers.