Does Riding a Bicycle Increase Testosterone?
by Benjamin Bunting BA(Hons) PGCert
Written by Ben Bunting: BA(Hons), PGCert. Sport & Exercise Nutrition. British Army Physical Training Instructor (MFT).
If you are suffering from low testosterone, you should know that cycling can help. Cycling is not only a great form of exercise, it can also help you increase your overall health. You can increase your testosterone naturally through diet and other lifestyle factors.
Aerobic exercise can increase testosterone
While aerobic exercise has been known to improve body composition and cardiovascular health, many individuals wonder if this type of physical activity also has an effect on testosterone (T) levels.
In the past, studies have reported that endurance exercise, weightlifting, and other types of resistance exercise have the potential to raise serum testosterone concentrations. However, the magnitude of the hormonal change induced by these exercises differs depending on gender, age, and body size. Currently, the impact of exercise on serum testosterone is unclear, and future studies will need to better understand the mechanisms of exercise and testosterone production.
Testosterone is produced by the testes, and it is an important hormone that can boost muscle growth. Higher T levels can help reduce the risk of developing a number of long-term illnesses. When testosterone levels are low, the body is less able to repair itself properly, leading to lower performance. Therefore, boosting T levels is an important goal for fitness and health.
Aerobic exercise is performed at a moderate to high intensity. As a result of the stress that is experienced during exercise, the neuroendocrine system produces cortisol and other stress hormones, which can negatively affect testosterone. Excessive cardio can lead to elevated levels of these hormones, which can affect the male's ability to perform physical activities.
The initial rise in plasma testosterone concentrations is secondary to the testicular stimulation that occurs during exercise. These effects are often mediated by increased ligand binding capacity and acute androgen receptor expression. Moreover, increased serum testosterone may activate the testosterone-androgen receptor signaling pathway, and increase the half-life of androgen receptor mRNA translation.
A recent study of obese and overweight men found that a 12-week aerobic exercise intervention significantly increased serum testosterone concentrations. The exercise program involved a 40-60 minute walking or jogging plan, 1-3 times a week.
Some studies have reported that resistance exercises, including weightlifting, are effective for enhancing serum testosterone concentrations, regardless of body weight.
Exercises that engage large muscle groups, such as weightlifting, are particularly effective in increasing testosterone levels. One study reported that after a 30-minute weightlifting session, T levels in men were 21.6 percent higher. Another study showed similar results in women.
While some research has indicated that increased testosterone levels are temporary, other research has suggested that the increases may be permanent. In addition to affecting testosterone, exercise can also reduce weight, improve blood pressure, and improve the overall mood. Additionally, it can improve heart health and control diabetes.
Excessive endurance exercise reduces testosterone
Excessive endurance exercise can negatively affect testosterone levels. These effects can result in decreased libido, fatigue, bone mineral content, and performance.
A number of studies indicate that long-distance runners and triathletes are most at risk for experiencing low testosterone levels. Testosterone deficiency can lead to poor muscle mass development, increased body fat, and reduced athletic performance.
One study, published in the Journal of Physiology, examined the effects of running at various intensities. After two hours of treadmill running, testosterone concentrations in serum were lower than the controls. However, the effects were not as dramatic as in age-matched controls.
Another study, conducted by VanBruggen and colleagues, compared the diffusion rates of hormonal compounds into saliva. The results revealed that serum testosterone and salivary testosterone were significantly reduced in both the high and low-intensity groups. They concluded that this reduction in testosterone was due to changes in the concentration gradients of hormonal substances.
One of the main reasons for low testosterone is overtraining. Overtraining results in elevated cortisol, which interferes with testosterone production.
In the 1970s, Dr. John Sutton conducted the first systematic study of exercise and testosterone in humans. He discovered that men participating in prolonged submaximal exercise had significantly lower testosterone levels than control subjects.
These findings led to the term "Exercise-Hypogonadal Male Condition" (EHMC). EHMC has been associated with a number of adverse effects on male and female reproductive health.
Men with EHMC exhibit significantly lower levels of testosterone, luteinizing hormone, and follicle-stimulating hormone. These effects are detrimental to male libido, fertility, and the ability to recover from exercise.
High-intensity athletes also experienced a significant decrease in FSH and sperm counts. While the exact reasons are not known, researchers speculate that the changes in these hormones might be attributed to changes in the hypothalamic-pituitary-testicular regulatory axis.
Cortisol and Performance in Professional Cyclists
Cortisol and testosterone concentrations play an important role in physical exercise. Their secretion has been shown to be sensitive to training stress. However, few studies have investigated how these hormones affect athletic performance. A few studies have investigated the relationship between salivary cortisol and testosterone levels and performance in triathlon competition.
The goal of this particular study was to evaluate whether salivary cortisol and testosterone concentrations were related to BMD in male competitive cyclists. Competitive cycling is a high-intensity sport involving intense exercise. In order to examine this, the researchers used an established method for measuring these hormones during a short triathlon competition.
Male cyclists aged 22-45 were recruited from regional and national cycling competitions. They completed a demographic questionnaire and a one-day dietary recall. Participants were also scanned for bone density. Several variables were measured including height, body mass index (BMI), years of cycling experience, and total body strength. Each participant was also provided with hospital scrubs for laboratory measurements.
The athletes perfromed a series of maximal workload training sessions with a slowly increasing protocol.
After collecting the salivary samples, they were stored on dry ice and analyzed within two days. These tests were performed by radioimmunoassay. Using the results of this study, the researchers hypothesized that a higher concentration of salivary cortisol and testosterone would predict a better performance of triathletes.
The study demonstrated that testosterone levels decreased and cortisol levels increased.
By all intents and purposes this would increase catbolism, which normally would suggest decrements in recovery and performance. However, this state did not reduce performance of the athletes or create an issue with overtraining.
Therefore, in professional athletes at least, this horonal change didn't cause any perfromance decrements.
Hormonal effect of consecutive races
Nine professional cyclists during the Tour of Spain stage race had their hormone levels monitored to understand the effects of long distances, long duration and minimal recovery on testosterone levels.
The results suggest that the endocrinological system can become exhausted after long term duration of exercise which resulted in decreased testosterone levels. This trend correlates with other studies examining hormonal changes in endurance trained individuals.
Mesocycle periodization training may help
The 55/80 interval training is a 30-min exercise session which alternates between a 55% and an 80% work rate. This type of training is often applied to high training volumes by cyclists. It is known to affect hormone levels, but the exact effect has been unknown.
These athletes typically cover annual distances of 26-32 000 km, and perform intense competitions. Studies have reported an increase in free testosterone and reduced markers related to RED-S. However, it is not clear whether these hormonal changes were due to the intensified mesocycle or simply energy compensation.
Researchers sought to determine the effects of the mesocycle on male cyclists. Twelve healthy, physically active males with previous experience with weightlifting and endurance were recruited. They performed five weeks of endurance training on a cycle ergometer. Participants followed a standardized strength training program, and were evaluated before and after the intervention. Testosterone and cortisol were measured at rest and before and after the workout.
Blood morphology and sex hormone-binding globulin were assessed in venous blood samples at rest. Total testosterone, free testosterone, and IGF-1 were also measured. In addition, a maximal incremental test (MI) was conducted before and after the program. Finally, the power output for the leg press and bench-press were measured.
Pre- and post-exercise results showed similar delta values for testosterone and cortisol. Delta cortisol changes were comparable from trial to trial over three days. There was a 38% increase in the maximum power for the bench-press, and a 22% increase in the maximum leg-press. During the 4-hour LIT session, repeated 30-second sprints were performed to improve knee extension torque. A recovery time of 30 seconds for peak knee extension torque was also measured.
While the results of this study suggest that the intensified mesocycle did not significantly impact hormonal responses, the participants' body composition remained unchanged from pre- to post-test. This may have been a protective mechanism to avoid overtraining.
Male endurance trained cyclists should be monitored for signs of overtraining. This is particularly important during the intense interval training phase of an exercise program. Several studies have shown that testosterone levels can be increased by short, intense interval workouts. Alternatively, a natural increase can be achieved through dietary habits and lifestyle practices. However, this method will not compare to a hormone replacement therapy.
An intensified mesocycle could have potentially induced testosterone levels in previously untrained male athletes. Although this has not been demonstrated, it is possible that the induced testosterone could be responsible for increased performance.
Because of the potential for hormonal changes, it is important to know what the exact effect of the mesocycle is. The intensity of the mesocycle, the amount of time spent on the exercise program, and the number of sessions may influence the effect.
Although research has shown that prolonged endurance exercise can negatively affect testosterone production, not all edurance athletes fall into this category. Instead, they can receive a minor boost in testosterone from the occasional bout of vigorous resistance training.
Although exercise can boost testosterone levels, it is important to be aware of the signs of overtraining. Overtraining can lead to fatigue, diminished libido, and chronic fatigue.
Therefore, to conclude, it seems that extreme and chronic sessions of endurance exercise commonly associated with long distances, long duration coupled with little recovery can negatively effect testosterone levels in athletes. However, these results did little to negatively impact the athlete's performance. On the other hand we have little available research demonstrating the effects of excessive endurance cycling on recreational athletes.