Doctors and fitness professionals still have a lot to learn about exercise and its effects on testosterone. If you’re a man with low testosterone, exercise may help. Testosterone levels can also run low if you’re overtraining or have low energy availability (eating too little to support your training demands). Despite strength training four days a week, he wasn’t feeling motivated by his lifestyle changes. That’s why suppressing estradiol (e.g. with high doses of medications such as anastrozole) has been shown to worsen insulin resistance and fat mass. Specifically, motor unit losses of 47% have been reported in older (60–81 years) compared to younger (22–38 years) participants . A gradual decrease in the number of muscle fibres begins during the 5th decade of life with an approximate 50% reduction by 80 years . The selective atrophy of type II muscle fibres with age decreases the maximum relaxation rate , which can be ascribed to decreased sarcoplasmic reticulum activity and reduced sliding speed of actin on myosin 127, 128. Interpretation of this disparate literature should be compared to the results of an RCT comparing exercise and T effects, summarised in Fig. Masculinizing hormone therapy generally enhances strength and power, potentially improving performance. Feminizing hormone therapy generally reduces strength and power, potentially affecting performance in sports requiring those attributes. Upper body muscles tend to be more affected than lower body muscles due to the higher concentration of androgen receptors in the upper body. The rate of muscle growth varies depending on individual factors and exercise habits. Estrogen, while also having some anabolic effects, generally has a weaker influence on muscle development in comparison to testosterone. For most people, the best strategy is to focus on a balanced fitness routine that includes strength training, cardio, and healthy lifestyle habits that support long-term health. A balanced routine that includes strength training, cardio, and low-impact workouts can support overall health, fitness, and long-term performance. In many cases, the increase in testosterone in women is temporary but still supports muscle adaptation. Sheikholeslami-Vatani et al. investigated the acute effect of different resistance exercise orders on serum testosterone concentrations in untrained normal weight and obese men. So far, we have discussed works done in lean, young men; however, body weight and aging are inversely related to serum testosterone concentrations . Similar findings were also reported by Kreamer et al. further confirming the importance of a combination of various factors to mount significant increases in the post-exercise concentrations of serum testosterone. Another possible explanation for this hormonal change is the involvement of larger muscle mass, which, in addition to resistance, may be required to induce significant acute changes in plasma testosterone concentrations. Free weight exercises induced a greater increase in plasma testosterone concentrations than did the machine weight exercises. A major determinant for this increase in plasma testosterone concentrations is the muscle mass used. Multiple studies have shown that resistance exercise can cause acute changes in serum testosterone concentrations. This can be manifested by an initial rise in plasma testosterone concentrations secondary to a catecholamine surge and testicular stimulation, followed by increases in cortisol levels, a hormone that inhibits testosterone production . In summary, resistance exercise appears to be a direct stimulant to testosterone production when sufficient muscle mass load is met, or when a moderate and higher exercise intensity is combined with larger muscle volume and shorter resting periods between the sets. Resistance exercise, also known as strength and weight training, involves the voluntary activation of specific skeletal muscles against some form of external resistance. Kraemer et al. reported that, when the number of repetitions during exercise was kept constant, the intensity determined the degree of acute post-exercise increase in serum testosterone concentrations. Significant increases in the serum testosterone concentrations were seen only in the high intensity exercise group. A small 2020 study with postmenopausal women found that 8 weeks of resistance training improved muscle mass and strength. However, a larger 2021 study with male and female participants found that BCAAs may not preserve lean body mass in people following a weight loss program. Harness the power of unconventional workouts for strength gains and discover unique exercises that could transform your fitness routine forever. Aim for 7-9 hours of quality sleep each night to support your body’s natural hormone production. If you’re not getting enough sleep duration or quality, your hormone levels can suffer. When you’re stressed, your body produces cortisol, which can hinder testosterone production. Always prioritize proper form to avoid injury, and consider pairing jump training with strength workouts for an ideal hormonal boost. These high-intensity workouts not only improve your power and speed but also enhance hormonal responses, including testosterone production. Summary of trials which have independently modified T levels within the physiological range, or utilised exercise training interventions, or combined these interventions. Furthermore, our exercise intervention consisted of both aerobic and resistance training, making direct comparisons with the above meta-analysis difficult. Given that muscle mass in the lower extremities is an important determinant of mobility status with aging 89, 90, our results may have implications for older men unable to exercise due to disease or disability. This highlights the paucity of data surrounding the effects of T and exercise training on aging in apparently healthy men, without major medical comorbidities. However, given the extensive evidence of the anabolic effects of T, coupled with the known association of low muscle mass and all-cause mortality in men , these findings may have important implications for men with reduced muscle mass resulting from their inability to exercise due to disease or disability. In older adults (≥ 65 years), an ‘umbrella review’ concluded that T administration was justified as a pharmacological intervention in men with low baseline T levels (6.9–10.4 nmol/L) to improve muscle mass .
