Influence of vitamin D supplementation on muscle strength and exercise capacity  in South African schoolchildren: Secondary outcomes from a randomised controlled trial (ViDiKids)

Keren Middelkoop; Lisa K. Micklesfield; Stephanie  Hemmings; Neil Walker; Justine Stewart; David A. Jolliffe; Amy E. Mendham; Jonathan C. Y. Tang; Cyrus Cooper; Nicholas C. Harvey; Robert J. Wilkinson; Adrian R. Martineau

Influence of vitamin D supplementation on muscle strength and exercise capacity in South African schoolchildren: Secondary outcomes from a randomised controlled trial (ViDiKids)

Keren Middelkoop, Lisa K. Micklesfield, Stephanie Hemmings, Neil Walker, Justine Stewart, David A. Jolliffe, Amy E. Mendham, Jonathan C. Y. Tang, Cyrus Cooper, Nicholas C. Harvey, Robert J. Wilkinson, Adrian R. Martineau (Lead Author)

Research output: Contribution to journal › Article › peer-review

Abstract

Objective: To determine whether vitamin D supplementation influences grip strength, explosive leg power, cardiorespiratory fitness and risk of exercise-induced bronchoconstriciton (EIB) in South African schoolchildren.

Methods: Sub-study (n=450) in Cape Town schoolchildren aged 8-11 years, nested within a phase 3 randomised placebo-controlled trial (ViDiKids). The intervention was weekly oral doses of 10,000 IU vitamin D3 (n=228) or placebo (n=222) for 3 years. Outcome measures were serum 25-hydroxyvitamin D3 (25[OH]D3) concentrations, grip strength, standing long jump distance, peak oxygen uptake (VO2peak , determined using 20-metre multi-stage shuttle run tests) and the proportion of children with EIB, measured at end-study.

Results: 64.7% of participants had serum 25(OH)D3 concentrations <75 nmol/L at baseline. At 3-year follow-up, children randomised to vitamin D vs. placebo had higher mean serum 25(OH)D3 concentrations (97.6 vs. 58.8 nmol/L respectively; adjusted mean difference [aMD] 39.9 nmol/L, 95% CI 36.1 to 43.6). However, this was not associated with end-study differences in grip strength, standing long jump distance, VO2peak , or risk of EIB.

Conclusion: A 3-year course of weekly oral supplementation with 10,000 IU vitamin D3 elevated serum 25(OH)D3 concentrations in South African schoolchildren but did not influence muscle strength, exercise capacity or risk of EIB.

Original language	English
Journal	BMJ Open Sport and Exercise Medicine
Publication status	Accepted/In press - 23 Aug 2024

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ViDiKids_CT_exercise_R1_accepted_23AUG24
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Cite this

Middelkoop, K., Micklesfield, L. K., Hemmings, S., Walker, N., Stewart, J., Jolliffe, D. A., Mendham, A. E., Tang, J. C. Y., Cooper, C., Harvey, N. C., Wilkinson, R. J., & Martineau, A. R. (Accepted/In press). Influence of vitamin D supplementation on muscle strength and exercise capacity in South African schoolchildren: Secondary outcomes from a randomised controlled trial (ViDiKids). BMJ Open Sport and Exercise Medicine.

Middelkoop, Keren ; Micklesfield, Lisa K. ; Hemmings, Stephanie ; Walker, Neil ; Stewart, Justine ; Jolliffe, David A. ; Mendham, Amy E. ; Tang, Jonathan C. Y. ; Cooper, Cyrus ; Harvey, Nicholas C. ; Wilkinson, Robert J. ; Martineau, Adrian R. / Influence of vitamin D supplementation on muscle strength and exercise capacity in South African schoolchildren: Secondary outcomes from a randomised controlled trial (ViDiKids). In: BMJ Open Sport and Exercise Medicine. 2024.

@article{5bde3840608d420394d37e06f937ffe3,

title = "Influence of vitamin D supplementation on muscle strength and exercise capacity in South African schoolchildren: Secondary outcomes from a randomised controlled trial (ViDiKids)",

abstract = "Objective: To determine whether vitamin D supplementation influences grip strength, explosive leg power, cardiorespiratory fitness and risk of exercise-induced bronchoconstriciton (EIB) in South African schoolchildren. Methods: Sub-study (n=450) in Cape Town schoolchildren aged 8-11 years, nested within a phase 3 randomised placebo-controlled trial (ViDiKids). The intervention was weekly oral doses of 10,000 IU vitamin D3 (n=228) or placebo (n=222) for 3 years. Outcome measures were serum 25-hydroxyvitamin D3 (25[OH]D3) concentrations, grip strength, standing long jump distance, peak oxygen uptake (VO2peak , determined using 20-metre multi-stage shuttle run tests) and the proportion of children with EIB, measured at end-study. Results: 64.7% of participants had serum 25(OH)D3 concentrations <75 nmol/L at baseline. At 3-year follow-up, children randomised to vitamin D vs. placebo had higher mean serum 25(OH)D3 concentrations (97.6 vs. 58.8 nmol/L respectively; adjusted mean difference [aMD] 39.9 nmol/L, 95% CI 36.1 to 43.6). However, this was not associated with end-study differences in grip strength, standing long jump distance, VO2peak , or risk of EIB. Conclusion: A 3-year course of weekly oral supplementation with 10,000 IU vitamin D3 elevated serum 25(OH)D3 concentrations in South African schoolchildren but did not influence muscle strength, exercise capacity or risk of EIB.",

author = "Keren Middelkoop and Micklesfield, {Lisa K.} and Stephanie Hemmings and Neil Walker and Justine Stewart and Jolliffe, {David A.} and Mendham, {Amy E.} and Tang, {Jonathan C. Y.} and Cyrus Cooper and Harvey, {Nicholas C.} and Wilkinson, {Robert J.} and Martineau, {Adrian R.}",

note = "Data availability statement: Anonymised data are available from corresponding authors upon reasonable request, subject to terms of IRB and regulatory approval. Funding information: This research was funded by the UK Medical Research Council (refs MR/R023050/1 and MR/M026639/1, both awarded to ARM). RJW was supported by Wellcome (104803, 203135). He also received support from the Francis Crick Institute which is funded by Cancer Research UK (FC2112), the UK Medical Research Council (FC2112) and Wellcome (FC2112). NCH and CC are supported by the UK Medical Research Council [MC_PC_21003; MC_PC_21001]. RJW is also supported in part by the NIHR Biomedical Research Centre of Imperial College NHS Trust. ",

year = "2024",

month = aug,

day = "23",

language = "English",

journal = "BMJ Open Sport and Exercise Medicine",

issn = "2055-7647",

publisher = "BMJ Publishing Group",

}

Middelkoop, K, Micklesfield, LK, Hemmings, S, Walker, N, Stewart, J, Jolliffe, DA, Mendham, AE, Tang, JCY, Cooper, C, Harvey, NC, Wilkinson, RJ & Martineau, AR 2024, 'Influence of vitamin D supplementation on muscle strength and exercise capacity in South African schoolchildren: Secondary outcomes from a randomised controlled trial (ViDiKids)', BMJ Open Sport and Exercise Medicine.

Influence of vitamin D supplementation on muscle strength and exercise capacity in South African schoolchildren: Secondary outcomes from a randomised controlled trial (ViDiKids). / Middelkoop, Keren; Micklesfield, Lisa K.; Hemmings, Stephanie ; Walker, Neil; Stewart, Justine; Jolliffe, David A.; Mendham, Amy E.; Tang, Jonathan C. Y.; Cooper, Cyrus; Harvey, Nicholas C.; Wilkinson, Robert J.; Martineau, Adrian R. (Lead Author).

In: BMJ Open Sport and Exercise Medicine, 23.08.2024.

Research output: Contribution to journal › Article › peer-review

TY - JOUR

T1 - Influence of vitamin D supplementation on muscle strength and exercise capacity in South African schoolchildren: Secondary outcomes from a randomised controlled trial (ViDiKids)

AU - Middelkoop, Keren

AU - Micklesfield, Lisa K.

AU - Hemmings, Stephanie

AU - Walker, Neil

AU - Stewart, Justine

AU - Jolliffe, David A.

AU - Mendham, Amy E.

AU - Tang, Jonathan C. Y.

AU - Cooper, Cyrus

AU - Harvey, Nicholas C.

AU - Wilkinson, Robert J.

AU - Martineau, Adrian R.

N1 - Data availability statement: Anonymised data are available from corresponding authors upon reasonable request, subject to terms of IRB and regulatory approval. Funding information: This research was funded by the UK Medical Research Council (refs MR/R023050/1 and MR/M026639/1, both awarded to ARM). RJW was supported by Wellcome (104803, 203135). He also received support from the Francis Crick Institute which is funded by Cancer Research UK (FC2112), the UK Medical Research Council (FC2112) and Wellcome (FC2112). NCH and CC are supported by the UK Medical Research Council [MC_PC_21003; MC_PC_21001]. RJW is also supported in part by the NIHR Biomedical Research Centre of Imperial College NHS Trust.

PY - 2024/8/23

Y1 - 2024/8/23

N2 - Objective: To determine whether vitamin D supplementation influences grip strength, explosive leg power, cardiorespiratory fitness and risk of exercise-induced bronchoconstriciton (EIB) in South African schoolchildren. Methods: Sub-study (n=450) in Cape Town schoolchildren aged 8-11 years, nested within a phase 3 randomised placebo-controlled trial (ViDiKids). The intervention was weekly oral doses of 10,000 IU vitamin D3 (n=228) or placebo (n=222) for 3 years. Outcome measures were serum 25-hydroxyvitamin D3 (25[OH]D3) concentrations, grip strength, standing long jump distance, peak oxygen uptake (VO2peak , determined using 20-metre multi-stage shuttle run tests) and the proportion of children with EIB, measured at end-study. Results: 64.7% of participants had serum 25(OH)D3 concentrations <75 nmol/L at baseline. At 3-year follow-up, children randomised to vitamin D vs. placebo had higher mean serum 25(OH)D3 concentrations (97.6 vs. 58.8 nmol/L respectively; adjusted mean difference [aMD] 39.9 nmol/L, 95% CI 36.1 to 43.6). However, this was not associated with end-study differences in grip strength, standing long jump distance, VO2peak , or risk of EIB. Conclusion: A 3-year course of weekly oral supplementation with 10,000 IU vitamin D3 elevated serum 25(OH)D3 concentrations in South African schoolchildren but did not influence muscle strength, exercise capacity or risk of EIB.

AB - Objective: To determine whether vitamin D supplementation influences grip strength, explosive leg power, cardiorespiratory fitness and risk of exercise-induced bronchoconstriciton (EIB) in South African schoolchildren. Methods: Sub-study (n=450) in Cape Town schoolchildren aged 8-11 years, nested within a phase 3 randomised placebo-controlled trial (ViDiKids). The intervention was weekly oral doses of 10,000 IU vitamin D3 (n=228) or placebo (n=222) for 3 years. Outcome measures were serum 25-hydroxyvitamin D3 (25[OH]D3) concentrations, grip strength, standing long jump distance, peak oxygen uptake (VO2peak , determined using 20-metre multi-stage shuttle run tests) and the proportion of children with EIB, measured at end-study. Results: 64.7% of participants had serum 25(OH)D3 concentrations <75 nmol/L at baseline. At 3-year follow-up, children randomised to vitamin D vs. placebo had higher mean serum 25(OH)D3 concentrations (97.6 vs. 58.8 nmol/L respectively; adjusted mean difference [aMD] 39.9 nmol/L, 95% CI 36.1 to 43.6). However, this was not associated with end-study differences in grip strength, standing long jump distance, VO2peak , or risk of EIB. Conclusion: A 3-year course of weekly oral supplementation with 10,000 IU vitamin D3 elevated serum 25(OH)D3 concentrations in South African schoolchildren but did not influence muscle strength, exercise capacity or risk of EIB.

M3 - Article

JO - BMJ Open Sport and Exercise Medicine

JF - BMJ Open Sport and Exercise Medicine

SN - 2055-7647

ER -