A marathon PB is built on more than carbon shoes. Three blood markers quietly shape how strong you feel on race day.
In 2026, the technology in running shoes is incredible. We have carbon plates, super foams, and GPS watches that tell us our exact recovery time. But the most important technology isn't on your feet. It's inside your veins.
If you are training for a marathon, you are asking your body to perform at its absolute limit. To hit a personal best, your internal systems need to be perfectly calibrated. Here are three markers that quietly shape your race-day performance:
Vitamin D isn't just for bone health. It's a pro-hormone that directly affects muscle fibre contraction and explosive power. Even in sunny Australia, many runners are deficient because we train in the early morning or late evening. Low vitamin D is a common contributor to the heavy-leg feeling in the final 10km of a marathon.
Running a marathon creates systemic inflammation. If your baseline inflammation (CRP) is already high due to poor recovery or diet, you may be at higher risk of injury during your peak training weeks. Monitoring CRP helps you judge when to push and when to take an extra rest day.
B12 is essential for red blood cell production. If your B12 is sub-optimal, your aerobic ceiling is lowered. You might find your heart rate spiking higher than it should at your goal marathon pace.
At SuperRun, we believe every runner should have access to their own data. No waiting weeks for a GP appointment. Just order your test, visit a collection centre, and get your data.
This article is general information for runners and is not medical advice, a diagnosis, or a treatment plan. Always consult a qualified professional before making major dietary or training changes.
SuperRun is blood testing built for runners. The Elite panel tracks 70+ biomarkers across hormones, heart, metabolism and longevity, scored against athlete performance zones. No GP referral needed, with 4,000+ collection centres across Australia.
