Why Exercise is Like Falling in Love

by Adam Toffan, M.Sc, NSCA-CSCS, CSEP-CEP Assistant Fitness Training and Assessment Coordinator, Recreation Services at the University of Manitoba

---

This week we celebrate the love of fitness.

Exercise has many similar hormonal responses to ones we have when falling in love. If you, or someone you know, has ever said they are in a relationship with the gym, they aren’t too far off. There are thought to be three stages of falling in love: lust, attraction and attachment. Each stage comes with different hormonal responses that you also see with exercise. 

During the lust stage of a relationship, the body increases the production of testosterone and estrogen. From a relationship standpoint, this is critical for reproduction, a driving force in the chemical attraction between people. From a fitness perspective, we need these hormones for bone and muscle growth. They also have a positive effect on fat levels and mood. Exercise boosts the production of testosterone, and production increases incrementally through a maintained exercise plan. Resistance training tends to have the greatest effect on testosterone levels. In females, there is a similar effect on testosterone levels, although there is much less testosterone. Estrogen is the female sex hormone. Aerobic and anaerobic exercise has been found to have a beneficial effect on estradiol levels, lean mass and fat mass. 

The attraction stage of love is similar in feeling to the effect of certain drugs and alcohol. We experience euphoria with a release of several chemicals in the brain, including dopamine, adrenaline, serotonin and norepinephrine, which are referred to as endorphins. These chemicals are responsible for the sensations of pleasure, fight or flight, focus and alertness, respectively, resulting in an addictive rush. Like love, exercise results in increases in dopamine stores and dopamine receptor generation that leaves us feeling energetic, motivated, focused and happy. Serotonin is important in the exciting feeling and diverts your attention to your love interest. Aerobic exercise improves mood by increasing serotonin levels in the brain, and endorphins are the cause of “runner’s high,” which is a euphoria combined with reduced anxiety and reduced ability to feel pain. Serotonin is also the chemical that depression medication aims to balance as it is responsible for improved mood and sleep. 

In the final phase of love, attachment, dopamine release and norepinephrine are replaced with oxytocin (the cuddle hormone) and vasopressin (the commitment hormone), which creates a long-lasting bond between two people. Oxytocin is released during childbirth and during sexual intercourse and promotes bonding between mother and child or adults. Vasopressin is also released after intercourse and is responsible for a monogamous, lifelong commitment. Intense exercise or moderate-intensity exercise for long durations have been shown to increase vasopressin concentration. This results in a love and dedication to exercise that will keep you going for the long haul.

Love and exercise have many shared effects, which explain why they both make us so happy. There are many reasons to love fitness, including the effects it has on your health and how it makes us feel. Everyone loves the feeling of being in love. To add more love to your life, find an exercise modality you enjoy and fall in love with fitness.

Sources

---

Esch, T and Stefano, G.B. (2005). “The Neurobiology of Love,” Neuroendocrinology Letters, No. 3. Vol. 26. Pp. 175 – 192. 

Kraemer, W.J., Ratamess, N.A. (2005). “Hormonal Responses and Adaptations to Resistance Exercise and Training,” Sports Medicine. Vol. 35(4). Pp. 339 – 361.

Smith, A.J., Phipps, W.R., Kurzer, M.S. (2013). “The Effects of Aerobic Exercise on Estrogen Metabolism in Healthy Premenopausal Women,” Cancer Epidemiology, biomarkers and prevention. Vol 22(5). Pp. 756 – 764.