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 An eye disease called age-related macular degeneration (AMD). 2  Some research shows that taking vitamin B12 with other vitamins, including folic acid and vitamin B6, might help prevent an eye disease called age-related macular degeneration. Injecting vitamin B12 as a shot, as well as taking through the nose or by mouth, is effective for treating low red blood cell counts caused by poor absorption of vitamin B12. 2  Vitamin B12 deficiency. 3  Taking vitamin B12 by mouth, through the nose, or as a shot is effective for treating vitamin B12 deficiency.