Abstract
A placebo-controlled, depletion-repletion protocol was utilized to examine the effect of vitamin C status on substrate utilization during a 90 min walk at 50% maximal oxygen consumption (VO2max). Nine vitamin C depleted subjects (plasma vitamin C < 28 μmol/L) agreed to participate in the 5-week study (aged, 27.6 ± 2.5 years, mean ± SE; 5 females, 4 males). Subjects were apparently healthy but unaware of their vitamin C status. Prior to the experimental period, VO2max was measured using open-circuit spirometry during a graded walking protocol. Subjects ingested a placebo capsule daily during weeks 1-3 and a 500 mg vitamin C capsule daily during weeks 4-5 of the experimental study. Mean plasma vitamin C rose nearly 3-fold and mean plasma carnitine fell by nearly 20% at repletion (week 5) versus depletion (week 3). At the end of weeks 3 and 5, subjects completed a 90 minute treadmill walk at an exercise intensity of 50% VO(2max). The relative contribution of fat utilized for energy during walking did not differ in the vitamin C depleted versus repleted states. However, work performed by subjects and gross efficiency during exercise increased significantly at repletion versus depletion (10% and 15%, respectively). These data indicate that vitamin C depletion is associated with reduced work efficiency during submaximal exercise.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 41-44 |
| Number of pages | 4 |
| Journal | International Journal for Vitamin and Nutrition Research |
| Volume | 69 |
| Issue number | 1 |
| State | Published - Jan 1999 |
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Keywords
- Exercise performance
- Substrate utilization
- Vitamin C status
- Work efficiency
ASJC Scopus subject areas
- Medicine (miscellaneous)
- Food Science
Cite this
Substrate utilization and work efficiency during submaximal exercise in vitamin C depleted-repleted adults. / Johnston, Carol; Swan, Pamela; Corte, Corinne.
In: International Journal for Vitamin and Nutrition Research, Vol. 69, No. 1, 01.1999, p. 41-44.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Substrate utilization and work efficiency during submaximal exercise in vitamin C depleted-repleted adults
AU - Johnston, Carol
AU - Swan, Pamela
AU - Corte, Corinne
PY - 1999/1
Y1 - 1999/1
N2 - A placebo-controlled, depletion-repletion protocol was utilized to examine the effect of vitamin C status on substrate utilization during a 90 min walk at 50% maximal oxygen consumption (VO2max). Nine vitamin C depleted subjects (plasma vitamin C < 28 μmol/L) agreed to participate in the 5-week study (aged, 27.6 ± 2.5 years, mean ± SE; 5 females, 4 males). Subjects were apparently healthy but unaware of their vitamin C status. Prior to the experimental period, VO2max was measured using open-circuit spirometry during a graded walking protocol. Subjects ingested a placebo capsule daily during weeks 1-3 and a 500 mg vitamin C capsule daily during weeks 4-5 of the experimental study. Mean plasma vitamin C rose nearly 3-fold and mean plasma carnitine fell by nearly 20% at repletion (week 5) versus depletion (week 3). At the end of weeks 3 and 5, subjects completed a 90 minute treadmill walk at an exercise intensity of 50% VO(2max). The relative contribution of fat utilized for energy during walking did not differ in the vitamin C depleted versus repleted states. However, work performed by subjects and gross efficiency during exercise increased significantly at repletion versus depletion (10% and 15%, respectively). These data indicate that vitamin C depletion is associated with reduced work efficiency during submaximal exercise.
AB - A placebo-controlled, depletion-repletion protocol was utilized to examine the effect of vitamin C status on substrate utilization during a 90 min walk at 50% maximal oxygen consumption (VO2max). Nine vitamin C depleted subjects (plasma vitamin C < 28 μmol/L) agreed to participate in the 5-week study (aged, 27.6 ± 2.5 years, mean ± SE; 5 females, 4 males). Subjects were apparently healthy but unaware of their vitamin C status. Prior to the experimental period, VO2max was measured using open-circuit spirometry during a graded walking protocol. Subjects ingested a placebo capsule daily during weeks 1-3 and a 500 mg vitamin C capsule daily during weeks 4-5 of the experimental study. Mean plasma vitamin C rose nearly 3-fold and mean plasma carnitine fell by nearly 20% at repletion (week 5) versus depletion (week 3). At the end of weeks 3 and 5, subjects completed a 90 minute treadmill walk at an exercise intensity of 50% VO(2max). The relative contribution of fat utilized for energy during walking did not differ in the vitamin C depleted versus repleted states. However, work performed by subjects and gross efficiency during exercise increased significantly at repletion versus depletion (10% and 15%, respectively). These data indicate that vitamin C depletion is associated with reduced work efficiency during submaximal exercise.
KW - Exercise performance
KW - Substrate utilization
KW - Vitamin C status
KW - Work efficiency
UR - http://www.scopus.com/inward/record.url?scp=0032995139&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032995139&partnerID=8YFLogxK
M3 - Article
C2 - 10052020
AN - SCOPUS:0032995139
VL - 69
SP - 41
EP - 44
JO - Internationale Zeitschrift fur Vitaminforschung. International journal of vitamin research. Journal international de vitaminologie
JF - Internationale Zeitschrift fur Vitaminforschung. International journal of vitamin research. Journal international de vitaminologie
SN - 0300-9831
IS - 1
ER -