What Free Testosterone tells you
Hormones are chemical messengers involved in energy, mood, body composition, and reproductive health. This group covers the key hormones a clinician may review when looking at these areas.
Which Honed panels include Free Testosterone
Free Testosterone is measured in the Hormone Panel. Every sample is collected at a pathology collection centre and processed at a NATA-accredited laboratory against RCPA reference ranges, with personalised plain-English commentary in your secure online report.
Why Free Testosterone matters
Free testosterone is the unbound, biologically active fraction of testosterone circulating in the blood (typically 1–3% of total testosterone). While most testosterone is bound to sex hormone-binding globulin (SHBG) and albumin, only the free fraction can enter cells and exert its effects on muscle, bone, and mood. Free testosterone is a more direct measure of androgen activity at the tissue level than total testosterone alone.
The range explained
Low levels
Low free testosterone (below 225 pmol/L in men) may indicate reduced bioavailable testosterone despite adequate total levels, particularly if SHBG is elevated. This can affect muscle-building capacity and recovery.
Normal range
Reference ranges: typically 225–725 pmol/L in adult men and 0–100 pmol/L in women. These represent the fraction of testosterone that is free and able to act on tissues.
High levels
Elevated free testosterone (above 725 pmol/L in men) is less common and may require investigation. It can occur with hormonal disruption or exogenous hormone use.
What affects Free Testosterone
- Training: Resistance exercise increases free testosterone production. SHBG is lowered by intense training, which can increase the proportion of testosterone that remains free.
- Nutrition: Adequate protein, fat, and minerals support free testosterone. Excess body fat increases SHBG, reducing free testosterone; conversely, very low body fat may impair overall testosterone production.
- Sleep: Sleep deprivation reduces free testosterone despite potentially normal total levels. Consistent sleep supports hormonal balance.
- Stress: Chronic stress raises SHBG and cortisol, reducing free testosterone availability. Stress management improves free testosterone relative to total.
When to retest
Every 8–12 weeks when monitoring performance; every 12 months for general health. Retest alongside total testosterone and SHBG for interpretation.
Why athletes care
Athletes value free testosterone because it represents the hormone available to drive muscle protein synthesis and recovery. A high free testosterone-to-SHBG ratio is associated with better athletic performance.
Related hormones markers
FAQ
What does the Free Testosterone blood test measure?
The unbound, biologically active fraction of testosterone. It is usually reviewed alongside total testosterone and SHBG to give a fuller picture.
Which Honed Health panels include Free Testosterone?
Free Testosterone is included in the Hormone panel.
What unit is Free Testosterone measured in?
Free Testosterone is reported in pmol/L, measured at NATA-accredited laboratories against RCPA reference ranges, with personalised plain-English commentary in your secure report.