Researchers studied how intense exercise affects three important hormones in the body: growth hormone, testosterone, and cortisol. They compared elite male gymnasts to regular active men and tested how their bodies responded to short bursts of maximum effort exercise using their upper and lower body muscles. They also looked at vitamin D levels to see if they played a role. The gymnasts’ bodies showed different hormone responses than the control group, especially after upper body exercise. Vitamin D appeared to influence how the body’s hormones changed after exercise. This research suggests that years of gymnastics training may train the body to handle intense exercise differently.

The Quick Take

  • What they studied: How the body’s hormone levels change during and after intense, short-burst exercise in elite gymnasts compared to regular active people, and whether vitamin D status affects these changes.
  • Who participated: 15 elite male artistic gymnasts (average age 21.3 years) and 14 physically active men (average age 20.2 years) who served as a comparison group.
  • Key finding: Elite gymnasts showed higher growth hormone and testosterone levels immediately after upper-body intense exercise compared to the control group, while their cortisol (stress hormone) didn’t increase as much. Vitamin D levels appeared to influence how testosterone and cortisol responded to lower-body exercise.
  • What it means for you: Years of gymnastics training may help the body adapt to intense exercise by changing how it produces hormones. Vitamin D may play a role in how your body responds to exercise, though more research is needed to understand this connection fully. This doesn’t mean non-gymnasts should expect the same results.

The Research Details

This study brought together 29 young men—15 elite gymnasts and 14 regular active men—and had them perform two different intense exercise tests. The first test focused on upper body muscles, and the second focused on lower body muscles. Both tests involved maximum effort for short periods (called Wingate Anaerobic Tests). The researchers took blood samples at three points: before exercise, immediately after, and 60 minutes after. They measured three hormones (growth hormone, testosterone, and cortisol) and vitamin D levels using laboratory equipment that detects these substances in the blood.

The study design allowed researchers to compare how gymnasts’ bodies responded differently than regular active men’s bodies. By testing both upper and lower body separately, they could see if different muscle groups caused different hormone responses. The timing of blood samples helped them understand how quickly hormones changed and how long those changes lasted.

Understanding how intense exercise affects hormones is important because these hormones control muscle growth, energy, and stress response. By comparing elite gymnasts to regular active men, researchers could see if years of training actually change how the body handles extreme exercise. Looking at vitamin D adds another layer because vitamin D affects many body systems, including hormone production. This approach helps explain why some athletes might recover differently or build muscle differently than others.

This study is relatively small (29 participants), which means the results should be viewed as preliminary. The participants were all young men, so results may not apply to women or older people. The study was well-designed with clear measurement methods and multiple time points for blood collection. However, the study only looked at one type of exercise test, so we don’t know if results would be the same for other types of intense activity. The researchers used established laboratory methods to measure hormones and vitamin D, which increases reliability.

What the Results Show

Elite gymnasts performed significantly better on the upper-body intense exercise test compared to the control group when their performance was adjusted for body weight. This makes sense because gymnasts train their upper bodies extensively.

When it came to hormones, gymnasts showed notably higher growth hormone and testosterone levels immediately after the upper-body exercise test. Growth hormone is important for muscle growth and recovery, while testosterone supports muscle development and strength. The gymnasts’ bodies appeared to produce more of these muscle-building hormones in response to upper-body exercise.

Interestingly, cortisol (the stress hormone) behaved differently. While both groups’ cortisol levels increased after exercise, the increase was smaller in gymnasts compared to the control group. This suggests that gymnasts’ bodies may be better adapted to handle intense exercise stress.

Vitamin D levels appeared to influence hormone responses, but the relationship was complex. In the control group, higher vitamin D at the start was linked to bigger cortisol increases after lower-body exercise, but smaller testosterone increases after lower-body exercise.

The study found that the type of exercise (upper body versus lower body) mattered for hormone responses. Upper-body exercise produced more noticeable differences between gymnasts and control group members. This suggests that the body’s hormone response to exercise depends on which muscles are being used. The vitamin D connection was only clearly seen in the control group for lower-body exercise, suggesting that training background might change how vitamin D influences hormone response.

Previous research has shown that intense exercise increases growth hormone and testosterone while also increasing cortisol. This study confirms those findings but adds important new information: elite training appears to amplify the muscle-building hormone response (growth hormone and testosterone) while dampening the stress hormone response (cortisol). The vitamin D connection is newer territory—while scientists knew vitamin D affects hormones, this study provides specific evidence about its role during exercise recovery.

The study only included 29 young men, all in their early 20s, so results may not apply to women, older adults, or younger people. The study didn’t measure other factors that might affect hormones, like sleep, diet, or stress levels outside the study. Only one type of intense exercise was tested, so we don’t know if results apply to other forms of exercise like running or swimming. The study was done at one point in time, so we don’t know if these patterns stay the same throughout the year or change with seasons (which could affect vitamin D). Finally, the study can show relationships between variables but cannot prove that one causes the other.

The Bottom Line

Based on this research, there is moderate evidence that elite gymnastics training creates adaptive changes in how the body produces hormones during intense exercise. For people interested in optimizing their exercise response, maintaining adequate vitamin D levels appears important, though more research is needed. If you’re doing intense exercise training, monitoring your vitamin D status through blood tests (if recommended by your doctor) may be worthwhile. However, this research is preliminary and shouldn’t replace personalized advice from a doctor or sports medicine professional.

This research is most relevant to elite gymnasts, coaches working with gymnasts, and sports scientists studying how training affects the body. It may also interest people doing intense strength or power training who want to understand their body’s hormonal responses. People concerned about vitamin D and exercise performance should pay attention. However, casual exercisers or people doing moderate activity don’t need to change their routine based on this single study. People with hormone-related health conditions should consult their doctor before making changes based on this research.

The hormone changes measured in this study happened immediately and within 60 minutes after exercise. However, the adaptive changes in how elite gymnasts’ bodies respond to exercise develop over years of training. If someone wanted to see similar adaptations, it would take months to years of consistent, intense training. Vitamin D status changes more slowly—it typically takes weeks to months to significantly raise vitamin D levels through supplementation or sun exposure.

Want to Apply This Research?

  • Track intense exercise sessions (type, duration, and intensity) alongside vitamin D intake or supplementation. Note any changes in recovery speed, muscle soreness, or energy levels. If possible, track mood and stress levels, as cortisol affects these. Users could rate their perceived recovery on a 1-10 scale after intense workouts.
  • Users doing intense exercise training could use the app to ensure they’re getting adequate vitamin D through diet, supplementation, or sun exposure. They could set reminders for vitamin D intake and track it alongside their intense workout sessions. The app could provide education about vitamin D sources and help users identify if they might benefit from vitamin D testing through their doctor.
  • Over 8-12 weeks, users could track the relationship between their vitamin D status and how they feel after intense exercise sessions. They could note patterns like whether they recover faster on days when they’ve had adequate vitamin D intake. The app could generate reports showing correlations between vitamin D tracking and recovery metrics, helping users understand if vitamin D supplementation makes a practical difference for them personally.

This research is preliminary and based on a small study of young male gymnasts. The findings should not be used to diagnose, treat, or prevent any medical condition. Hormone levels are complex and influenced by many factors beyond exercise and vitamin D. Before making changes to your exercise routine, vitamin D supplementation, or if you have concerns about your hormone levels, consult with a qualified healthcare provider or sports medicine physician. This article is for educational purposes only and does not replace professional medical advice. Individual responses to exercise and vitamin D vary greatly, and what works for elite gymnasts may not apply to the general population.