This post is for informational purposes. Reference ranges vary between laboratories and clinical guidelines. Discuss your results with a qualified GP or sports medicine physician — do not adjust training, medication, or supplementation based on this post alone.

Every distance runner should have 8–10 specific tests annually, not to get a race participation certificate, but to catch the conditions that erode performance before they become medical problems. The most common are iron deficiency (ferritin below 30 µg/L impairs aerobic performance before anaemia develops), vitamin D deficiency (endemic across most populations), and early cardiac abnormalities that only surface under exercise load. Together, these tests take one GP appointment and one fasting blood draw. The return is a clear picture of whether your body is supporting the training you’re putting into it.

Use our running calculator to track your training paces alongside your health data, and build your season around a structured training plan that matches the physiological picture your tests reveal.

Why Runners Need Annual Health Monitoring

Running places specific demands on the body that general health screening doesn’t fully capture. A recreational runner training 50–70km per week is putting their cardiovascular system, iron stores, hormonal axis, bone density, and kidney function under sustained load that the average sedentary person never experiences. The tests that matter for runners aren’t always the same tests that matter for the general population.

Before we build any season, I want to know the athlete’s ferritin, their vitamin D, their haemoglobin, and their thyroid. Those four numbers tell me whether we’re starting the build on solid ground or trying to construct a training programme on a compromised physiological foundation. Training on iron deficiency is like trying to run with the handbrake on.

1. Full Blood Count (FBC / General Blood Test)

When: Once a year, fasting. More frequently, if you’re a high-mileage runner, vegan, or female with heavy periods.

What it tests: Red blood cells, white blood cells, haemoglobin, haematocrit, and platelets.

Why runners need it: Haemoglobin carries oxygen in red blood cells. Low haemoglobin — clinical anaemia — directly reduces VO2 max and aerobic capacity. It causes the flat, heavy feeling in training that many runners attribute to overtraining when the actual cause is inadequate oxygen-carrying capacity.

White blood cell counts outside the normal range can signal infection, inflammation, or immune suppression — the latter being a documented consequence of sustained very high training loads.

What to watch: Haemoglobin below 130 g/L (men) or 120 g/L (women) warrants investigation. Note that haemoglobin can be normal while iron stores are depleted — see ferritin below.

2. Ferritin (Stored Iron) — The Most Important Test for Runners

When: Once a year minimum; twice a year for female runners, vegan runners, or any runner with recurring fatigue.

What it tests: The body’s stored iron reserves, reflecting total iron availability rather than just circulating levels.

Why it matters more than haemoglobin alone: Ferritin depletes before haemoglobin falls. A runner with ferritin of 18 µg/L may have perfectly normal haemoglobin — and will still experience measurable impairment in aerobic performance, increased perceived effort at equivalent paces, and slower recovery. Sports medicine research consistently shows performance begins to decline at ferritin below 20–30 µg/L even without clinical anaemia.

Most sports medicine physicians recommend targeting serum ferritin above 50 µg/L for competitive runners. Values below 30 µg/L warrant dietary intervention and often supplementation; values below 15 µg/L typically require supervised supplementation.

Who is most at risk: Female runners (menstrual iron loss), vegan and vegetarian runners (lower bioavailability of plant-based non-haem iron), runners with heavy training loads (haemolysis from foot-strike impact), and runners who chronically undereat. For a complete guide to iron management on a plant-based diet, see our vegan runner nutrition guide.

What to ask your GP for: “I’d like a ferritin test alongside my FBC.” It is often not included in standard annual blood panels unless specifically requested.

3. Vitamin D

When: Once a year, ideally in late winter or early spring when levels are typically at their annual nadir.

What it tests: Serum 25-hydroxyvitamin D [25(OH)D] — the storage form of vitamin D in the body.

Why runners need it: Vitamin D deficiency is endemic — estimated to affect 40–50% of the global population at any given time, with higher rates in northern latitudes during winter. For runners specifically, vitamin D deficiency is associated with increased stress fracture risk (by impairing bone mineralisation), reduced muscle recovery, suppressed immune function, and impaired cardiac contractility.

Reference ranges: Most labs define deficiency below 50 nmol/L (20 ng/mL) and insufficiency between 50–75 nmol/L. Many sports medicine practitioners and endocrinologists recommend athletes target 75–100 nmol/L for optimal musculoskeletal and immune function.

What to do about deficiency: UK Public Health guidance recommends 10 mcg (400 IU) daily supplementation for all adults during autumn and winter. Many sports medicine practitioners recommend 25 mcg (1,000 IU) for runners, particularly those training predominantly indoors or in northern climates. Vegan runners should specify lichen-derived D3 or D2.

4. Iron Panel (Serum Iron, TIBC, Transferrin Saturation)

When: If ferritin is low or you have persistent fatigue despite normal FBC.

What it tests: The full iron metabolism picture — circulating iron, the body’s iron-carrying capacity (TIBC), and the percentage of that capacity currently occupied (transferrin saturation).

Why it adds to ferritin alone: A complete iron panel distinguishes true iron deficiency from anaemia of chronic disease (where iron is low but stores are normal — a different treatment pathway) and from haemolytic anaemia from foot-strike impact. This distinction matters because supplementing iron when stores are adequate is not helpful and may cause side effects.

5. Blood Glucose (Fasting)

When: Once a year, fasting (no food for at least 8 hours beforehand, no carbohydrates the previous evening).

What it tests: Fasting blood glucose, reflecting insulin function and metabolic health.

Reference ranges: Normal fasting glucose: 3.9–5.6 mmol/L. Impaired fasting glucose (pre-diabetes): 5.6–6.9 mmol/L. Diabetes diagnostic threshold: ≥7.0 mmol/L on two separate occasions.

Why runners need it: Regular moderate-intensity running is one of the most effective lifestyle interventions for maintaining healthy blood glucose and improving insulin sensitivity. This test confirms the benefit is being realised — and can catch early metabolic dysfunction in runners who are training hard but not managing nutrition carefully.

Elevated fasting glucose in an active runner warrants referral to an endocrinologist. It is not a reason to stop exercising — quite the opposite.

6. Cardiac Assessment (ECG and Echocardiogram)

When: At minimum once, then as advised by your cardiologist. Annually for runners over 40 or those with cardiac risk factors.

What it tests: ECG (electrocardiogram) assesses heart rhythm and electrical conduction. Echocardiogram (ultrasound of the heart) assesses structural integrity — valve function, chamber size, wall motion, and ejection fraction.

Why runners need it: The cardiovascular benefits of running are well-established. But sustained high training volumes — particularly in Masters runners (over 40) — are associated with a small but real increased risk of atrial fibrillation, myocardial fibrosis, and coronary artery calcification in the most extreme training groups. These risks are relevant primarily for runners with very high lifetime mileage, not for recreational runners training at typical volumes.

More importantly, an ECG at rest can detect pre-existing conduction abnormalities (including hypertrophic cardiomyopathy — the leading cause of sudden cardiac death in young athletes) before they become a problem during high-intensity exercise.

For runners over 40 and new to vigorous exercise: The American Heart Association recommends an exercise stress test (ECG under increasing exercise load) before beginning high-intensity training. This is particularly important for runners with a family history of cardiac disease, hypertension, diabetes, or dyslipidaemia.

For practical heart rate monitoring and training zone guidance, see our heart rate while running guide.

7. Blood Pressure

When: Annually at minimum; more frequently if readings are elevated or if you have a family history of hypertension.

How: At rest, seated, arm supported. Avoid caffeine, exercise, and smoking for 30 minutes before measurement. Take two or three readings and use the average.

Reference ranges (AHA/ACC 2017):

Category	Systolic	Diastolic
Normal	< 120 mmHg	< 80 mmHg
Elevated	120–129 mmHg	< 80 mmHg
Stage 1 hypertension	130–139 mmHg	80–89 mmHg
Stage 2 hypertension	≥ 140 mmHg	≥ 90 mmHg

Why runners need it: Running measurably reduces resting blood pressure one of its most consistent cardiovascular benefits. However, runners are not immune to hypertension, and assuming fitness equals healthy blood pressure is a mistake. High blood pressure increases the risk of stroke, heart attack, and kidney disease. It also increases cardiovascular risk during hard training sessions.

Running in significant heat with unmanaged hypertension carries additional risk. Any reading consistently above 130/80 warrants a GP assessment rather than continued monitoring at home.

8. Lipid Panel (Cholesterol)

When: Once a year, fasting.

What it tests: Total cholesterol, LDL (“bad” cholesterol), HDL (“good” cholesterol), and triglycerides.

Why runners need it: Endurance running typically improves the lipid profile — raising HDL and lowering triglycerides. However, some runners are genetically predisposed to elevated LDL regardless of fitness level (familial hypercholesterolaemia), and this cannot be managed through training alone.

What to watch: LDL above 3.0 mmol/L, triglycerides above 1.7 mmol/L, or HDL below 1.0 mmol/L (men) / 1.2 mmol/L (women) in the context of other risk factors warrants discussion with your GP.

9. Creatinine and Creatinine Kinase (CK)

When: Once a year, or after episodes of unusually heavy training.

What it tests: Creatinine reflects kidney filtration function. Creatinine kinase (CK) is an enzyme released by damaged muscle cells — a direct marker of muscle breakdown.

Why runners need it: Creatinine slightly elevates in runners due to higher muscle mass, so reference ranges should be interpreted with this context in mind. Significant elevation warrants kidney function assessment. Elevated CK after normal training may indicate overtraining, insufficient recovery, or a specific muscle injury that hasn’t yet produced obvious symptoms. Very high CK (above 1,000 U/L outside of the immediately post-race context) can indicate rhabdomyolysis — muscle breakdown at a scale that can cause acute kidney injury, which requires urgent medical assessment.

Note: Regular NSAID use (ibuprofen, naproxen) can temporarily elevate creatinine — another reason to limit anti-inflammatory drug use during heavy training blocks.

10. Thyroid Function (TSH, Free T3, Free T4)

When: Once a year.

What it tests: TSH (thyroid-stimulating hormone) from the pituitary gland, and free T3 and T4 (active thyroid hormones) from the thyroid gland.

Why runners need it: Thyroid hormones regulate metabolism, energy production, body temperature regulation, heart rate, and mood. Hypothyroidism (underactive thyroid) causes fatigue, weight gain, cold intolerance, and impaired recovery — all of which mimic overtraining syndrome and are frequently misattributed to training load. Hyperthyroidism (overactive thyroid) causes palpitations, weight loss, heat intolerance, and anxiety.

A note on endurance athletes and thyroid: Research suggests that high-volume endurance training can suppress TSH and free T3 levels temporarily — sometimes called “low T3 syndrome” or “euthyroid sick syndrome” — without underlying thyroid disease. This is why clinical context matters: a borderline low TSH in a runner doing 90+ km per week should be interpreted differently than in a sedentary person. Discuss with your GP or an endocrinologist.

11. General Urinalysis

When: Once a year.

What it tests: Urine protein, glucose, red blood cells, white blood cells, and specific gravity — providing a broad picture of kidney and urinary tract health.

Why runners need it: Temporary haematuria (blood in urine) and mild proteinuria (protein in urine) can occur after very long or very hard runs due to the mechanical stress on the kidneys. These findings should resolve within 48–72 hours post-run. Persistent abnormalities — particularly haematuria or significant proteinuria — warrant nephrology referral. Running itself does not cause kidney disease, but pre-existing kidney conditions can be exacerbated by significant dehydration during training. Our hydration guide covers kidney-protective hydration strategies.

Summary: Annual Tests by Priority

Test	Frequency	Especially important for
Full Blood Count (FBC)	Annual	All runners
Ferritin	Annual (twice for high-risk groups)	Women, vegans, high-mileage runners
Vitamin D	Annual (late winter)	All runners, especially northern latitudes
Iron panel	If ferritin low or fatigue persists	Runners with low ferritin
Fasting blood glucose	Annual	All runners
ECG / Echocardiogram	Annual for 40+; once for all	Over 40s, family cardiac history
Blood pressure	Annual	All runners
Lipid panel	Annual	All runners; especially family history of heart disease
Creatinine and CK	Annual or post-heavy block	High-mileage, NSAID users
Thyroid (TSH, T3, T4)	Annual	All runners; especially those with fatigue or weight changes
Urinalysis	Annual	All runners