Tibial Stress Fracture — Biomarkers & Genes Summary Biomarker / Gene Bad Score Free Actions Paid Actions BIOMARKERS Vitamin D (25-OH) <30 ng/mL Midday sun; fatty fish D3 3–5k IU; K2 MK-7; Magnesium P1NP <35 mcg/L Non-impact load; 8+ hrs sleep Collagen peptides + Vit C; Zinc CTX >0.573 ng/mL Reduce load; fix energy deficit Omega-3 2–3g; Calcium 1000mg PTH >55 pg/mL Weight-bearing exercise; sun D3 + K2 + Magnesium glycinate Estradiol & Testosterone <30 pg/mL (women) Restore energy; sleep 8–9h Zinc 25mg; Boron 3–6mg; HRT IGF-1 <150 ng/mL Sleep 8–9h; resistance training Zinc 15–25mg; Creatine 3–5g GENETIC VARIANTS COL1A1 (rs1800012) TT genotype Soft surface; 10% mileage cap Vit C; Collagen 10g; Copper 2mg VDR (multiple variants) Variant alleles High-calcium foods; exercise D3 to 60–80 ng/mL; Magnesium ESR1 (rs2234693) PvuII/XbaI variants Resistance training; soy/flax Boron 3–6mg; Vit D 60–70 ng/mL LRP5 (rs4988321) A1330V variant 50–100 jumps 3–5×/week Vit D 60–70 ng/mL; Vibration TNFRSF11B / OPG Low-OPG expression Anti-inflammatory diet; fish Omega-3 2–4g; K2 MK-7; Mag Sources: peer-reviewed literature on tibial stress fractures, bone biomarkers and sports genomics