Iron deficiency shows up in 50-70% of endurance athletes, which directly compromises oxygen delivery to working muscles and brain during efforts. When hemoglobin and myoglobin can't transport adequate oxygen, ATP production slows and performance drops measurably. First Endurance Multi V addresses this with Ferrochel ferrous bisglycinate, a chelated iron form that delivers high bioavailability without the gastric distress or mineral absorption interference that non-chelated iron causes. The formula pairs iron with folate, B12, and choline to support red blood cell formation—the complete oxygen transport infrastructure rather than isolated supplementation.

Chromium handles glucose and fatty acid metabolism through insulin potentiation, which matters when you're consuming high carbohydrate loads during training blocks. ChromMax chromium picolinate helps partition nutrients toward muscle glycogen storage rather than fat accumulation, supporting body composition over months of consistent use. This works alongside B-complex vitamins that convert carbohydrates, fats, and branched-chain amino acids into ATP through multiple enzymatic pathways. Thiamin, riboflavin, niacin, B6, pantothenic acid, and biotin all function as coenzymes in energy production—deficiencies in any single vitamin create metabolic bottlenecks that limit performance regardless of training quality.

The antioxidant matrix combines Spectra Total ORAC5 Blend (29 concentrated fruit, vegetable, and herb extracts), ginkgo biloba, and green tea extract to address exercise-induced oxidative stress without interfering with training adaptation. High-dose single antioxidants can blunt the cellular signaling that drives fitness gains, but balanced, broad-spectrum antioxidant activity from whole food concentrates supports recovery while preserving adaptation. Vitamin C at 444% DV and vitamin E at 200% DV provide water-soluble and fat-soluble antioxidant protection respectively, while selenium functions as the cofactor for glutathione peroxidase, the most quantitatively important cellular antioxidant enzyme.... Read More