Peace through strength... but first you need to get strong. These nutrient deficiencies lead to more injuries and less adaptation.
If Pete Hegseth, Secretary of War, gets his way, the US military is about to get fitter. Hegseth said he was tired of seeing fat troops, and training guidelines will be restored to what they should be – scary and tough.
But just like with athletic training, troop training can be a double-edged sword. We can train harder and longer, but can we recover and adapt to the heavier training load? Planned well, we finish stronger and faster. Planned poorly, we finish weaker, slower, and injured.
An overlooked difference-maker? Nutrition, particularly getting enough vitamin D ➔ Buy at Biotest. A new study sheds some light.
The OCS study
This study followed Marine Officer candidates (177 men, 50 women) through 10 weeks of intense training to see how vitamin D and iron status affected their health and injury risk.
The Officer Candidate School's physical training includes long-distance runs, interval sprints and hill runs, obstacle courses, circuit training, farmers-walking ammo cans over rough terrain, rucks with 60 pounds of gear, and more. Think of it as doing CrossFit and strongman training, while preparing for a half-marathon, all day long... with weapons.
Researchers examined whether vitamin D and iron status were associated with bone health, injury risk, and structural bone changes during the training period. Here's what they found:
- Both nutrients dropped during training, and those who started deficient had worse bone strength outcomes and a higher risk of musculoskeletal injuries compared to those with optimal levels.
- In particular, low vitamin D and poor iron regulation were linked to weaker bone adaptations under stress, while higher baseline hepcidin (an iron regulatory hormone that reduces iron absorption/mobilization) predicted more injuries in men.
- Keeping vitamin D and iron levels dialed in before and during demanding training directly influences bone resilience and injury risk.
- The decline in micronutrient status suggests that the physiological demands of training exceed participants' ability to maintain optimal levels under a usual diet.
- Having better vitamin D and iron/ferritin appears tied to more favorable bone adaptation (less fatigability, better strength outcomes) and lower risk of bone stress injury.
- The authors suggest that screening and optimizing vitamin D and iron status before training might help reduce risk and improve readiness.
How to use this info
This study shows that people low on those micronutrients are more prone to injuries and can't adapt as well to tough training.
In the study, women were hardest hit by iron deficiencies because they were more likely to start with lower iron stores. The men tolerated the decline better, but they weren't immune. However, men seldom need iron supplementation outside of extreme training conditions.
Vitamin D is different. Most Americans are either deficient or insufficient to begin with, and strenuous exercise elevates inflammatory cytokines and increases the conversion of vitamin D to inactive metabolites. Low vitamin D status blunts bone strength gains and increases vulnerability to injury.
Now, most of us aren't entering into a 10-week Marine training program, but we do train hard, and sometimes we increase training volume and push our limits.
The fix? Microencapsulated D3. Microencapsulation ramps up the bioavailability of vitamin D3 – much more is absorbed and utilized by the body. The same delivery system also allows for sustained release, so it's easy to maintain steady levels in the bloodstream.
D Fix ➔ Buy at Biotest contains 5000 IU of microencapsulated vitamin D3. Use it before you begin a period of increased training volume.
For more info, check out: Vitamin D and the underdosing epidemic.
Reference
- Sekel, Nicole M., et al. "Micronutrient Status During Military Training and Associations With Musculoskeletal Health, Injury, and Readiness Outcomes." International Journal of Sport Nutrition and Exercise Metabolism, vol. 34, no. 6, 2024, pp. 378–390. Human Kinetics.