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How Free Testosterone Impacts Female Energy Levels

Understand the significance of free testosterone in women and the factors that can influence its levels to take targeted action for optimal health

Daniesha Govender
By Daniesha Govender
Korana Braun | Content Editor | InsideTracker
Edited by Korana Braun

Published June 20, 2024.

a man and a woman standing next to each other

Free testosterone, an unbound form of this hormone, significantly affects various physiological processes, such as muscle metabolism, energy production, and cognitive function.

It's essential to understand its importance and impact on female health, as imbalances can lead to symptoms like fatigue, decreased muscle strength, and mood fluctuations.

» Discover personalized strategies to optimize your hormone levels and reclaim your energy

What is free testosterone?

We often refer to testosterone as the "male hormone," but it's also essential for women. There are two main types: bound and unbound (also called free). The former attaches to proteins in the bloodstream, making them inactive, while the latter circulates freely and can directly influence your cells.

» Find out why women should care about testosterone

Free testosterone in women’s bloodstream significantly affects gynecological health. It can access cells in the body to maintain bone density, regulate sexual health, and help develop muscle.

» Discover the importance of SHBG and DHEAS biomarkers for women

How to measure free testosterone

To assess your levels, clinicians use total testosterone and a sex hormone-binding globulin test. Results show free testosterone in picograms per deciliter of blood (pg/dL) and total testosterone in nanograms per deciliter (ng/dL). A phlebotomist usually takes a blood sample for analysis, but there are also ongoing studies on saliva tests as a non-invasive alternative. [1]

» Unlock a deeper understanding of your health by measuring and optimizing your hormones

Free testosterone reference ranges

The normal range of free testosterone in females varies. Here are the references by age:

AgeNormal free testosterone levels
Age 301.2–6.4 pg/mL
Under 50Less than 1.5 pg/mL
Over 50Less than 1.0 pg/mL

Note: If you suspect a free testosterone imbalance, consult your doctor for proper diagnosis and treatment options.

» Assess your body’s hormone data to make targeted health changes

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Symptoms and factors influencing free testosterone imbalances in women

Lower levels of free testosterone in women cause fatigue, lethargy, depression, low libido, and irritability. On the other hand, higher leads to increased potential health risks like infertility, sleep apnea, and type 2 diabetes. [2,3,4]

The complex hormonal balance stems from the hypothalamus and pituitary gland. Age, menstrual cycle, physical activity, stress, and conditions like polycystic ovary syndrome can all influence it. [5] Physiological indicators like irregular menstrual cycles, increased fat, or lower muscle mass can also indicate a disturbance.

» Here's how to balance testosterone and estrogen in women

Note: If you're worried about free testosterone, consult your endocrinologist. They can examine your levels in context, determine the underlying causes, and suggest appropriate treatment.



Metabolic and physiological effects of free testosterone in the female body

Impact on vitality, cognition, and metabolic health in women

Through its anabolic effects on muscle mass and metabolism, free testosterone improves the conversion of nutrients into energy, enhancing women's energy levels.

» Understand the role of testosterone in the body

It also regulates energy metabolism through the following interactions with various organs and tissues:

  • Fat distribution through lipolysis
  • Mood and mental alertness regulation through neurotransmitter interaction [6,7]
  • Liver and pancreas function by influencing insulin sensitivity and glucose metabolism

» Unlock your energy potential: Get personalized science-backed recommendations for a healthy and active lifestyle

Impact on menstrual cycles, pregnancy, and menopause

Some women experience increased energy during specific periods of the menstrual cycle, specifically around ovulation. Hormonal shifts during pregnancy can also alter free testosterone, causing fatigue. [8] Additionally, free testosterone levels decline with age—especially during menopause—affecting energy, mood, and physical strength [9].

Impact on women's physical performance and endurance

Beyond its impact on energy, free testosterone is linked to physical performance in women, influencing muscle strength and exercise capacity. Optimal levels enhance athletic performance and endurance. [10]

» Explore our plans to improve your endurance and performance

Studies show strength training and high-intensity interval training (HIIT) may positively influence your levels, leading to improved muscle mass and overall energy. [11] But you should be careful. Excessive or prolonged strenuous workouts can result in hormonal imbalances that reduce free testosterone due to the body's stress response.

» Check out the low-impact exercise every HIIT regimen should include

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How to optimize free testosterone levels

Specific diet and lifestyle modifications can support a healthy balance. For example, avocados and nuts that are rich in healthy fats can help your levels, while excessive sugar and processed foods may have a negative impact. [12] Regular exercise, stress management, and adequate sleep can also optimize free testosterone levels.

» Improve your health span through nutrition, supplements, exercise, and lifestyle recommendations

  • Exercise regularly: Include strength training and HIIT workouts in your routine, but avoid overtraining [10, 11].
  • Eat a balanced diet: Focus on whole foods and healthy fats, and limit processed foods and sugar [12].
  • Manage stress: Practice stress-reduction techniques like yoga or meditation.
  • Get enough sleep: Aim for 7-8 hours of quality sleep each night.

Take charge of your vitality

Understanding the significance of free testosterone and taking proactive steps to maintain its optimal levels is critical to fostering a healthy lifestyle.

So, take charge of your energy and vitality—test your free testosterone levels and explore evidence-based strategies to optimize this crucial hormone. By prioritizing your hormonal balance, you can unlock a path to enhanced physical performance, cognitive function, and overall well-being.

» Discover your personal health analysis and data-driven wellness guide to help you live healthier, longer

Free testosterone, measured by blood tests, is the amount of active testosterone in the body that is not bound to a carrier like SHBG. InsideTracker Ultimate+Subscription plan offers free testosterone testing as part of 48 biomarker analyses, but this analysis is currently available only for men.




Disclaimer: InsideTracker doesn't diagnose or treat medical conditions. If you have any health concerns, consult your physician.