Every marker we test, explained

What it measures. The protein inside red blood cells that carries oxygen from your lungs to your muscles and organs, reported as a concentration in your blood.

Why it matters. Oxygen delivery is the foundation of endurance. Low haemoglobin (anaemia) usually shows up as tiredness, breathlessness on climbs and a slower recovery; it is one of the first numbers a doctor looks at.

What can move it. Iron, B12 and folate status, blood loss, altitude, hydration on the day (dehydration concentrates it), heavy training blocks and illness.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. How many red blood cells are in a given volume of blood.

Why it matters. Read together with haemoglobin and haematocrit, it shows whether you are making enough red cells and whether they are the right size.

What can move it. Iron, B12 and folate, altitude, hydration, smoking and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The proportion of your blood that is made up of red blood cells, as a percentage.

Why it matters. A quick gauge of oxygen-carrying capacity and of how concentrated your blood is. Endurance training tends to expand plasma volume, which can make haematocrit look a little lower without any real shortage of red cells.

What can move it. Hydration, altitude, training volume, iron status and blood loss.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Mean corpuscular volume: the average size of your red blood cells.

Why it matters. Small cells point towards iron deficiency; large cells point towards B12 or folate shortage or alcohol. It helps work out why haemoglobin is low.

What can move it. Iron, B12 and folate status, alcohol, thyroid function and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Mean corpuscular haemoglobin: the average amount of haemoglobin inside each red blood cell.

Why it matters. Low values usually travel with low iron; it supports the MCV reading.

What can move it. Iron status, B12 and folate, inherited red-cell traits.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Mean corpuscular haemoglobin concentration: how densely haemoglobin is packed into each red cell.

Why it matters. Another check on how well your red cells are built. Persistent low values usually mean iron is short.

What can move it. Iron status and some inherited red-cell conditions.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Red cell distribution width: how much your red blood cells vary in size.

Why it matters. A wide spread often means a mix of old and new cells of different sizes, which is an early sign that iron, B12 or folate is running short, sometimes before haemoglobin drops.

What can move it. Iron, B12 and folate status, recent blood loss or recovery from anaemia.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The small cell fragments that start clotting when you cut yourself.

Why it matters. Too few and you bruise or bleed easily; too many can follow inflammation, infection or iron deficiency. Hard training can nudge them briefly.

What can move it. Infection, inflammation, iron deficiency, some medicines and recent strenuous exercise.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Mean platelet volume: the average size of your platelets.

Why it matters. Larger platelets are younger and more active. Read alongside the platelet count rather than on its own.

What can move it. Platelet turnover, inflammation and some blood conditions.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The total number of white blood cells, the cells of your immune system.

Why it matters. High counts usually mean your body is fighting something or is inflamed; low counts can follow viral illness, heavy training stress or some medicines. A very hard session can raise it for a day.

What can move it. Infection, inflammation, stress hormones, recent hard exercise, smoking and medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The most common white blood cell, the first responders to bacterial infection and tissue damage.

Why it matters. Raised with bacterial infection, inflammation and after very hard efforts; low counts can leave you more open to infection.

What can move it. Infection, inflammation, steroids, intense exercise and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The white blood cells that fight viruses and remember past infections.

Why it matters. Raised with viral infections; a drop after prolonged heavy training is one of the classic signs of under-recovery.

What can move it. Viral illness, training load, sleep, stress and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. White blood cells that clear debris and damaged tissue and help direct the immune response.

Why it matters. Raised with longer-running infections and inflammation, and during recovery from illness.

What can move it. Infection, inflammation and recovery from illness.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. White blood cells involved in allergy and the response to parasites.

Why it matters. Raised with hay fever, asthma, eczema, allergies and some infections.

What can move it. Allergies, asthma, skin conditions, parasites and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The least common white blood cell, involved in allergic reactions and inflammation.

Why it matters. Usually low. A rise is uncommon and is read with the other white cells.

What can move it. Allergic reactions, some inflammatory conditions and, rarely, blood disorders.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. A waste product made when the body breaks down protein, cleared by the kidneys.

Why it matters. Rises when you are dehydrated, eating a lot of protein or when the kidneys are under strain. Common after a long race or a heavy training week.

What can move it. Hydration, protein intake, muscle breakdown, kidney function and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. A waste product of normal muscle turnover, cleared by the kidneys at a steady rate.

Why it matters. The main everyday check on kidney function. People with more muscle run naturally higher, and a hard session the day before can push it up temporarily.

What can move it. Muscle mass, recent intense exercise, hydration, creatine supplements and kidney function.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Estimated glomerular filtration rate: a calculation from your creatinine, age and sex that estimates how well your kidneys filter blood.

Why it matters. The standard way to read kidney function. It is an estimate, and it under-reads in very muscular people and after hard exercise, so a one-off low value is checked with a repeat.

What can move it. Creatinine, hydration, muscle mass, recent exercise and kidney health.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The main salt in your blood, which controls how much water your body holds and how nerves and muscles fire.

Why it matters. Tightly controlled. Low sodium can follow drinking far more than you sweat out on long events; high sodium usually means dehydration.

What can move it. Fluid balance, sweat losses, drinking habits during exercise and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. A mineral that keeps your heart rhythm and muscle contractions regular.

Why it matters. Both high and low values matter for the heart. A slightly raised result is often from the sample itself (hand clenching or a delay before analysis) rather than you.

What can move it. Kidney function, hydration, diet, medicines and sample handling.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. A salt that travels with sodium and helps keep your fluid and acid balance steady.

Why it matters. Read with sodium and bicarbonate to understand hydration and acid-base balance.

What can move it. Hydration, vomiting or diarrhoea, breathing and kidney function.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The main buffer in your blood that keeps its acidity in the normal range.

Why it matters. Low values point towards acid build-up (for example after a very hard effort or in some kidney conditions); high values towards vomiting or some medicines.

What can move it. Breathing, kidney function, intense exercise and fluid losses.

On these profiles: Health + Performance, The Complete Profile

What it measures. All the protein in your blood plasma, mostly albumin and globulins.

Why it matters. A broad check on nutrition, liver function and hydration.

What can move it. Hydration, diet, liver function, inflammation and immune activity.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The main protein made by the liver, which carries hormones, vitamins and drugs and keeps fluid inside your blood vessels.

Why it matters. Low albumin can mean the liver is struggling, protein intake is poor or there is long-running inflammation. It is also a marker of general nutrition.

What can move it. Diet, liver function, inflammation, hydration and kidney losses.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The group of proteins other than albumin, including the antibodies your immune system makes.

Why it matters. Raised with infections, inflammation and some immune conditions; low with some protein-losing conditions.

What can move it. Infection, inflammation, immune activity and liver function.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Alkaline phosphatase: an enzyme found mainly in the liver, bile ducts and bone.

Why it matters. Rises when bile flow is blocked or when bone is being remodelled, which is why it climbs during growth, after fractures and sometimes with heavy training.

What can move it. Bile duct and liver conditions, bone turnover, vitamin D status, pregnancy and growth.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. A yellow pigment produced when old red blood cells are broken down and processed by the liver.

Why it matters. High levels cause jaundice. Mildly raised bilirubin with everything else normal is common and usually harmless (Gilbert syndrome), and it rises a little after fasting or hard endurance efforts.

What can move it. Red cell breakdown, liver function, fasting, dehydration and inherited traits.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Alanine aminotransferase: an enzyme concentrated in liver cells that leaks into the blood when they are damaged.

Why it matters. The most specific everyday liver marker. Raised by fatty liver, alcohol, some medicines and viral hepatitis. Very hard exercise can lift it for a few days because muscle contains some ALT too.

What can move it. Alcohol, body fat, medicines and supplements, viral infections and recent intense exercise.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Aspartate aminotransferase: an enzyme found in the liver, heart and skeletal muscle.

Why it matters. Read with ALT. Because muscle contains a lot of AST, it is often raised after long or hard sessions; a liver problem usually raises ALT as much or more.

What can move it. Muscle damage from exercise, liver conditions, alcohol and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Gamma-glutamyl transferase: an enzyme in the liver and bile ducts that is sensitive to alcohol and bile-flow problems.

Why it matters. The liver marker most responsive to drinking. It also rises with fatty liver and some medicines, and helps decide whether a raised ALP is from the liver or from bone.

What can move it. Alcohol, body fat, medicines, bile duct conditions.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. All the cholesterol carried in your blood, across every type of particle.

Why it matters. A starting point for heart-health risk, but the breakdown (HDL, LDL, non-HDL, triglycerides and the ratios) matters more than the total on its own.

What can move it. Diet, body weight, exercise, genetics, thyroid function and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The main form of fat carried in your blood and stored for energy.

Why it matters. High levels go with excess calories, refined carbohydrate, alcohol and insulin resistance, and add to cardiovascular risk. They fall quickly with regular endurance exercise.

What can move it. Recent meals, alcohol, sugar and refined carbohydrate, body weight, exercise and genetics.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. High-density lipoprotein, the particle that carries cholesterol away from the arteries back to the liver.

Why it matters. Higher is generally better. Regular aerobic exercise is one of the most reliable ways to raise it.

What can move it. Exercise, body weight, smoking, alcohol, genetics and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Low-density lipoprotein, the particle most strongly linked to cholesterol building up in artery walls.

Why it matters. The number most guidelines use to judge long-term heart risk. It responds to diet, weight and, where needed, medication.

What can move it. Saturated fat intake, body weight, genetics, thyroid function and some medicines.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Your total cholesterol divided by your HDL.

Why it matters. A quick way to weigh the protective part against the whole. Lower ratios are better; it is used in UK heart-risk calculators.

What can move it. Anything that moves total cholesterol or HDL: diet, exercise, weight and genetics.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. HDL cholesterol as a percentage of your total cholesterol.

Why it matters. Another way of expressing the balance between protective and total cholesterol. Higher is better.

What can move it. Exercise, body weight, diet and genetics.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Very-low-density lipoprotein, the particle that carries triglycerides out of the liver, calculated from your triglyceride result.

Why it matters. Tracks triglycerides closely and rises with the same things: excess energy, alcohol and insulin resistance.

What can move it. Diet, alcohol, body weight and exercise.

On these profiles: The Baseline, The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Total cholesterol minus HDL: all the cholesterol carried in the particles that can build up in arteries.

Why it matters. Many clinicians prefer this to LDL because it captures every harmful particle and does not need a fasting sample.

What can move it. Diet, body weight, exercise, genetics and some medicines.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Apolipoprotein A1, the main protein on HDL particles.

Why it matters. A count of the protective particles rather than the cholesterol they carry; a more direct view of the HDL side of the picture.

What can move it. Exercise, body weight, diet and genetics.

On these profiles: Health + Performance, The Complete Profile

What it measures. Apolipoprotein B, the protein found once on every LDL, VLDL and related particle.

Why it matters. A count of the particles that can enter artery walls. Many specialists consider it the single best lipid marker of long-term cardiovascular risk.

What can move it. Saturated fat, body weight, insulin resistance, genetics and some medicines.

On these profiles: Health + Performance, The Complete Profile

What it measures. Your ApoB result divided by your ApoA1 result, calculated by the laboratory.

Why it matters. The balance between particles that deposit cholesterol and particles that remove it. Lower is better.

What can move it. Anything that moves ApoB or ApoA1: saturated fat, body weight, exercise, insulin resistance and genetics.

On these profiles: Health + Performance, The Complete Profile

What it measures. Glycated haemoglobin: the share of your haemoglobin with sugar attached, which reflects your average blood glucose over the last two to three months.

Why it matters. The standard test for diabetes and pre-diabetes, and a useful long-term view of blood-sugar control that a single glucose reading cannot give.

What can move it. Diet, body weight, exercise, sleep, some medicines and conditions that change red-cell lifespan (which can make it read falsely high or low).

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The same HbA1c result expressed as a percentage, the older DCCT unit, alongside the mmol/mol figure.

Why it matters. Provided so you can compare with older reports or non-UK references that still use percentages.

What can move it. Identical to HbA1c: diet, body weight, exercise, sleep and red-cell lifespan.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. High-sensitivity C-reactive protein, a protein the liver releases in response to inflammation, measured precisely enough to detect low-grade levels.

Why it matters. Persistent low-grade inflammation is linked to cardiovascular risk and poor recovery. It spikes with any infection or injury and for a few days after a very hard event, so timing matters.

What can move it. Infection, injury, recent hard exercise, body fat, sleep, smoking and gum disease.

On these profiles: The Baseline, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. A waste product from the breakdown of purines in food and in your own cells, cleared by the kidneys.

Why it matters. High levels can crystallise in joints (gout) and are linked with metabolic health. Dehydration and heavy exercise raise it; some endurance athletes run high after long events.

What can move it. Hydration, alcohol (especially beer), red meat and seafood, fructose, body weight, kidney function and some medicines.

On these profiles: The Health Profile, Health + Performance, The Complete Profile

What it measures. The iron circulating in your blood at the moment of the sample.

Why it matters. Swings through the day and after meals, so it is read with ferritin, transferrin and saturation rather than on its own.

What can move it. Time of day, recent meals and supplements, inflammation and iron stores.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The protein that stores iron, and the best everyday measure of how much iron you have in reserve.

Why it matters. Low ferritin is the most common nutritional problem in endurance athletes, especially women, and it hurts performance before anaemia appears. It also rises with inflammation, so a high value is not always good news.

What can move it. Iron intake and absorption, menstrual losses, sweat and foot-strike losses in runners, inflammation, infection and alcohol.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The protein that carries iron around the blood.

Why it matters. The body makes more when iron is short, so a high transferrin with a low ferritin confirms deficiency.

What can move it. Iron status, liver function, inflammation and pregnancy.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. How much iron your transferrin could carry if fully loaded, calculated from transferrin.

Why it matters. High when iron is short, low with inflammation or iron overload. Read with ferritin and saturation.

What can move it. Iron status, inflammation and liver function.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The percentage of your transferrin that is actually carrying iron.

Why it matters. Low saturation confirms that iron supply to the tissues is short; very high saturation can point to iron overload (haemochromatosis), which is worth knowing early.

What can move it. Iron intake, iron stores, inflammation and inherited iron-handling traits.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The total amount of vitamin B12 in your blood, needed to make red blood cells and keep nerves healthy.

Why it matters. Low B12 causes fatigue, large red cells and, if prolonged, nerve symptoms. It is more common in people eating little or no animal produce and in people on some long-term medicines.

What can move it. Diet, absorption from the gut, age, some medicines (including metformin and acid suppressants) and supplements.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance

What it measures. Holotranscobalamin: the part of your vitamin B12 that cells can actually take up and use.

Why it matters. A more sensitive check than total B12, useful when the total is borderline. Low active B12 shows a real shortage earlier.

What can move it. The same things that move total B12: diet, absorption, medicines and supplements.

On these profiles: The Complete Profile

What it measures. Vitamin B9 in your blood, needed alongside B12 to make red blood cells and DNA.

Why it matters. Low folate causes the same large-cell anaemia as low B12. It falls quickly with a poor diet because the body stores little of it.

What can move it. Green vegetables, pulses and fortified foods, alcohol, some medicines and absorption.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. 25-hydroxyvitamin D, the storage form of vitamin D made in your skin from sunlight and taken in from food and supplements.

Why it matters. Supports bone, muscle and immune function. Most people in the UK run low between October and March, and low levels are linked with stress fractures and more frequent illness in athletes.

What can move it. Sunlight on skin, season, latitude, skin colour, body weight, diet and supplements.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The calcium in your blood, most of it bound to albumin, needed for bones, muscle contraction and nerve signals.

Why it matters. Kept in a very tight range by the body. Results outside it usually point to parathyroid, vitamin D or kidney issues rather than diet.

What can move it. Albumin level, vitamin D, parathyroid hormone, kidney function and some medicines.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Your calcium result adjusted for your albumin level, calculated by the laboratory.

Why it matters. Because much of the calcium in blood rides on albumin, this corrected figure is the one to read if your albumin is low or high.

What can move it. The same things that move calcium and albumin.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. A mineral that works with calcium in bone and sits at the heart of how cells make and use energy.

Why it matters. Low phosphate can follow poor intake or refeeding after heavy restriction; high phosphate is mostly a kidney question.

What can move it. Diet, vitamin D, parathyroid hormone, kidney function and recent intense exercise.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. A mineral involved in muscle and nerve function, energy production and heart rhythm.

Why it matters. Low magnesium goes with cramps, poor sleep and irregular heartbeat, and is common with heavy sweating, alcohol and some medicines. Blood magnesium is a rough guide because most of the body's magnesium sits inside cells and bone.

What can move it. Diet (nuts, seeds, greens, wholegrains), sweat losses, alcohol, gut absorption and some medicines.

On these profiles: Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Thyroid-stimulating hormone from the pituitary gland, which tells the thyroid how much hormone to make.

Why it matters. The most sensitive single thyroid test. High TSH usually means an underactive thyroid (fatigue, weight gain, feeling cold, slow recovery); low TSH an overactive one.

What can move it. Thyroid health, iodine intake, some medicines, illness, pregnancy and time of day.

On these profiles: Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Free thyroxine, the main hormone the thyroid produces, measured as the unbound fraction that is available to tissues.

Why it matters. Read with TSH to confirm whether the thyroid itself is under- or overactive.

What can move it. Thyroid health, iodine, thyroid medication and some other medicines.

On these profiles: Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Free triiodothyronine, the active thyroid hormone most of which is made by converting T4 in the body.

Why it matters. Shows how much active hormone your tissues are getting. It can fall during very heavy training, illness or severe energy restriction even when TSH looks normal.

What can move it. Energy availability, training load, illness, selenium and iodine status and thyroid medication.

On these profiles: Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The main androgen hormone, measured as the total amount in your blood. Present in both men and women at very different levels.

Why it matters. Drives muscle repair, bone density, libido and drive. In men it falls with age, poor sleep and low energy availability; in women it is read alongside the other hormones for conditions such as PCOS.

What can move it. Sleep, body fat, training and energy availability, age, alcohol, stress and some medicines. Highest in the morning, so timing matters.

On these profiles: The Health Profile, Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Sex hormone binding globulin, the protein that carries testosterone and oestradiol in the blood and controls how much is free to act.

Why it matters. High SHBG means less free testosterone for the same total. It rises with low energy intake, thyroid overactivity and age, and falls with insulin resistance.

What can move it. Body weight, insulin resistance, thyroid function, oestrogen, age and energy availability.

On these profiles: Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Testosterone divided by SHBG, expressed as a percentage, as an estimate of how much testosterone is free to act.

Why it matters. A better guide than total testosterone when SHBG is unusually high or low.

What can move it. Anything that moves testosterone or SHBG: sleep, body weight, energy availability, thyroid function and age.

On these profiles: Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. Luteinising hormone from the pituitary gland, which drives testosterone production in men and ovulation in women.

Why it matters. Tells you whether a hormone problem starts in the brain or in the testes or ovaries. In women it varies through the cycle, so the day of your cycle matters.

What can move it. Cycle day, energy availability, stress, age and some medicines.

On these profiles: Women's Health + Performance, Health + Performance, The Complete Profile

What it measures. The main stress hormone, released by the adrenal glands in a daily rhythm that peaks in the morning.

Why it matters. Supports waking, blood sugar and the response to training. Persistently high or flattened cortisol goes with overtraining, poor sleep and chronic stress. Because it is a morning hormone, it should be drawn early.

What can move it. Time of day, sleep, stress, training load, illness and some medicines (including steroid inhalers and creams).

On these profiles: Health + Performance, The Complete Profile

What it measures. Dehydroepiandrosterone sulphate, an adrenal hormone and the body's most abundant steroid, which it converts into other hormones.

Why it matters. Falls steadily with age and with chronic stress. Read alongside cortisol and testosterone for a fuller picture of adrenal and hormonal balance.

What can move it. Age, stress, sleep and adrenal health.

On these profiles: Health + Performance, The Complete Profile

What it measures. The main form of oestrogen, which regulates the menstrual cycle, bone density and much more.

Why it matters. Low oestradiol in active women often signals low energy availability and raises the risk of stress fractures; it is a core part of the RED-S picture. In men a small amount is normal and important for bone.

What can move it. Cycle day, contraception, energy availability, body fat, age and menopause.

On these profiles: Women's Health + Performance

What it measures. Follicle-stimulating hormone from the pituitary, which matures eggs in women and supports sperm production in men.

Why it matters. With LH and oestradiol it shows where you are in your cycle and, in later life, whether perimenopause or menopause is under way.

What can move it. Cycle day, age, contraception and energy availability.

On these profiles: Women's Health + Performance

What it measures. An enzyme stored in muscle that leaks into the blood when muscle fibres are damaged.

Why it matters. The clearest single marker of muscle damage from training. It climbs for one to three days after hard or unfamiliar sessions and races, so a high value after a long run is expected; a high value at rest is not.

What can move it. Recent exercise, especially downhill or eccentric work, statins, muscle injury and some inherited traits.

On these profiles: Health + Performance, The Complete Profile

What it measures. The form of creatine kinase that is more specific to heart muscle.

Why it matters. Separates heart-muscle involvement from ordinary skeletal-muscle damage after exercise. Skeletal muscle contains a little CK-MB too, so it rises a bit after endurance events.

What can move it. Heart muscle stress, recent prolonged exercise and skeletal-muscle damage.

On these profiles: Health + Performance, The Complete Profile

What it measures. The oxygen-storing protein inside muscle fibres, released when muscle is damaged.

Why it matters. Rises and falls faster than creatine kinase, so it gives an early read on muscle damage after a hard session. Very high levels after extreme exertion need medical attention because they can strain the kidneys.

What can move it. Recent intense or prolonged exercise, muscle injury, heat illness and kidney function.

On these profiles: Health + Performance, The Complete Profile

What it measures. How the urine sample looks: colour and clarity.

Why it matters. Cloudy or dark urine can point to infection, dehydration or blood, and prompts a closer look at the other urine results.

What can move it. Hydration, diet, infection and some medicines and supplements.

On these profiles: The Complete Profile

What it measures. How acidic or alkaline the urine is.

Why it matters. Very acidic or very alkaline urine can reflect diet, infection or how the kidneys are handling acid, and affects whether crystals form.

What can move it. Diet, hydration, infection and some medicines.

On these profiles: The Complete Profile

What it measures. Whether protein is leaking into the urine.

Why it matters. Healthy kidneys keep protein in the blood. A trace after a hard run or race is common and clears within a day or two; persistent protein is a kidney check.

What can move it. Recent intense exercise, dehydration, fever, infection and kidney conditions.

On these profiles: The Complete Profile

What it measures. Whether sugar is spilling into the urine.

Why it matters. Normally absent. Glucose in urine usually means blood sugar has been high enough to overflow, which is a prompt to look at HbA1c.

What can move it. Blood glucose levels, some medicines and some kidney traits.

On these profiles: The Complete Profile

What it measures. Whether the body is burning fat for fuel hard enough to produce ketones that spill into urine.

Why it matters. Expected on a very low-carbohydrate diet or after a long fasted effort; otherwise it suggests the body is short of carbohydrate.

What can move it. Carbohydrate intake, fasting, prolonged exercise and uncontrolled diabetes.

On these profiles: The Complete Profile

What it measures. White blood cells in the urine.

Why it matters. A sign of inflammation or infection in the urinary tract, read with the bacterial count and culture.

What can move it. Urinary infection, inflammation and sample contamination.

On these profiles: The Complete Profile

What it measures. Red blood cells seen in the urine sample under the microscope.

Why it matters. Small amounts can appear after long runs (so-called runner's haematuria) and clear quickly; blood that persists is always worth a GP conversation.

What can move it. Recent prolonged exercise, infection, kidney stones, menstruation and kidney conditions.

On these profiles: The Complete Profile

What it measures. Cells shed from the lining of the urinary tract or skin that end up in the sample.

Why it matters. A few are normal. Many usually mean the sample picked up skin cells, which can make other urine results less reliable.

What can move it. How the sample was collected: a clean midstream catch keeps skin cells out.

On these profiles: The Complete Profile

What it measures. Tiny cylindrical structures formed inside the kidney tubules and washed out in the urine.

Why it matters. Most types point to the kidneys themselves rather than the bladder, so their presence is a prompt to look at kidney function.

What can move it. Kidney inflammation, dehydration and some kidney conditions.

On these profiles: The Complete Profile

What it measures. Mineral crystals that have formed in the urine.

Why it matters. Common when urine is concentrated and usually harmless; some types relate to kidney-stone risk or to uric acid.

What can move it. Hydration, urine pH, diet and uric acid levels.

On these profiles: The Complete Profile

What it measures. Yeast cells seen in the urine sample.

Why it matters. Usually contamination from the skin, occasionally a thrush infection.

What can move it. Sample collection, antibiotics, diabetes and immune status.

On these profiles: The Complete Profile

What it measures. How many bacteria are present in the sample.

Why it matters. High counts with white cells suggest a urinary infection; low counts are often contamination. The culture confirms it.

What can move it. Urinary infection and how the sample was collected.

On these profiles: The Complete Profile

What it measures. The laboratory grows any bacteria from the sample, identifies them and tests which antibiotics work against them.

Why it matters. The definitive check for a urinary infection, and the result a GP uses to choose the right antibiotic if one is needed.

What can move it. Urinary infection and sample collection; results take up to two days.

On these profiles: The Complete Profile