You hit your 40s and start noticing subtle but frustrating changes. Workouts don’t feel as effective. Energy dips earlier in the day. Sleep isn’t as restorative. Your motivation and focus aren’t quite what they used to be. You may even feel “off” without being able to pinpoint why. While aging is a natural part of life, these shifts can feel discouraging, especially when you’re still driven to stay active, strong, and sharp.
One possible explanation is declining testosterone. For many men, this hormonal change begins quietly and gradually after 40. At Genesis Lifestyle Medicine, men receive personalized hormone therapy to restore balance. Understanding how testosterone levels change with age, and whether testosterone therapy is right for you, is the first step toward reclaiming vitality.
What happens to testosterone after 40?
Testosterone is a primary male hormone responsible for muscle mass, bone density, metabolism, libido, mood, and cognitive function. Starting around age 30 to 40, testosterone levels typically decline by about 1% per year. This gradual decrease is considered normal and doesn’t always require treatment. However, some men experience a steeper drop that leads to noticeable symptoms. When testosterone levels fall below a healthy range, it is referred to as low testosterone, or “low T.” In these cases, testosterone therapy may be considered.
The following are some of the impacts of declining testosterone after 40:
- Declining energy and persistent fatigue: Low testosterone often shows up as ongoing exhaustion that doesn’t improve with rest. You may feel sluggish throughout the day, struggle to stay motivated, or rely more heavily on caffeine to function. This fatigue can make everyday tasks feel more difficult and reduce your desire to exercise or stay active.
- Loss of muscle mass and strength: Testosterone plays a key role in maintaining lean muscle. When testosterone levels drop, you may notice that building muscle becomes harder, workouts feel less productive, and strength declines despite consistent training. Over time, muscle loss can contribute to a slower metabolism and reduced physical performance.
- Increase in body fat and metabolic changes: Lower testosterone is linked to increased fat storage, particularly around the abdomen. This shift in composition can make weight gain easier and weight loss more difficult.
- Reduced libido and sexual performance: Testosterone influences sex drive and erectile function. A noticeable decrease in libido, difficulty maintaining erections, or reduced sexual satisfaction can be signs that hormone levels are no longer optimal.
- Mood changes and mental fog: Testosterone affects neurotransmitters in the brain that regulate mood and cognition. Low testosterone levels are often linked to irritability, low motivation, depression, anxiety, difficulty concentrating, and memory issues.
Benefits of testosterone therapy for men over 40
When blood testing confirms low testosterone and symptoms are present, testosterone therapy can offer meaningful improvements in multiple areas of health and well-being.
- Restored energy and stamina: Many men report feeling more alert, motivated, and capable of handling daily demands after starting therapy. Improved energy levels can make it easier to stay active, productive, and engaged.
- Improved muscle mass: Testosterone therapy helps support protein synthesis and muscle growth, allowing you to rebuild strength and maintain lean mass. This often translates into better workout performance and improved physical resilience.
- Healthier body composition: By supporting fat metabolism and muscle preservation, testosterone therapy can help shift body composition toward a leaner profile. Combined with proper nutrition and exercise, this may support weight management.
- Enhanced sexual health: Restoring testosterone to healthy levels can improve libido, erectile function, and sexual satisfaction, which often has a positive effect on confidence.
- Better mood and mental clarity: Balanced testosterone levels are associated with improved focus, sharper memory, and a more stable mood. Many men experience reduced brain fog and greater emotional well-being.
- Support for bone density: Testosterone plays a role in maintaining bone strength. Therapy may help reduce the risk of age-related bone loss and fractures over time.
Should you take testosterone therapy?
Testosterone therapy is not automatically recommended simply because you are over 40. The decision is based on a combination of symptoms, laboratory testing, and overall health.
You may be a candidate for testosterone therapy if:
- Blood tests confirm clinically low testosterone levels
- You are experiencing multiple symptoms that impact your quality of life
- Other potential causes, such as thyroid disorders or lifestyle factors, have been evaluated
Lifestyle improvements, such as better sleep, stress management, improved nutrition, and regular exercise, may support testosterone production and are often addressed first. If therapy is appropriate, treatment should always be customized and medically supervised.
At Genesis Lifestyle Medicine, hormone therapy is part of a personalized care model focused on long-term wellness. Ongoing monitoring ensures your levels remain within a healthy range and that your treatment stays aligned with your goals. Testosterone therapy is not about reversing age: it’s about restoring balance so your body can function the way it’s meant to.
Reclaim your vitality with Genesis Lifestyle Medicine
If you’re experiencing symptoms of low testosterone, the first step is proper testing and expert guidance. Genesis Lifestyle Medicine offers comprehensive hormone evaluations and therapy plans to help you feel stronger, more energized, and more confident. Schedule a consultation to find out whether testosterone therapy could be the right path forward for you.
