For females this would usually be finished in about 1 hour 15minutes. For males this would be finished in about 1 hour. Olympic distance triathlon (1500m / 40m bike / 10km run) For females this would take about 2 hours 25mins. For males this would take about 2 hours. Half Ironman (1.9km swim / 90km bike / 21km run) Females usually take about 5 hours 30mins.
Zinc. Night blindness may also be the result of a zinc deficiency which reduces the activity of an enzyme that helps the body produce vitamin A (retinol dehydrogenase). Research has shown that taking a zinc supplement is helpful. Healthcare providers often recommend 15 - 30 mg of zinc daily for vision.
1 Vitamin A and beta-carotene-necessary for night vision. 2  Vitamin B complex-the B complex vitamins may help prevent high homocysteine levels developing in the blood. 3  These are associated with vascular problems that affect the retina.4  Vitamin C-may reduce the risk of cataracts. Vitamin A and beta-carotene-necessary for night vision. 2  Vitamin B complex-the B complex vitamins may help prevent high homocysteine levels developing in the blood. 3  These are associated with vascular problems that affect the retina.