Strength training might offer more than just a fitter body. New research suggests that building muscle could play a role in lowering the risk of depression, with women showing the strongest benefits.

A recent study, published in the Journal of Affective Disorders, examined how different types of fitness affect mental health. The researchers found that genetic predispositions toward stronger muscles were linked to a lower likelihood of experiencing depression. Interestingly, the same link was not observed for cardiorespiratory fitness, which includes activities like running, cycling, or swimming.

Experts emphasize that this doesn’t mean cardio should be skipped—it still provides numerous health advantages—but it does highlight the unique role of strength training in mental well-being.

The Study at a Glance

Freepik | fxquadro | Researchers found that greater muscle strength links to a lower risk of depression in adults.

Researchers analyzed data from more than 341,000 adults, aged 37 to 73, participating in the UK Biobank, a large biomedical database. Using a method called Mendelian randomization, they investigated whether natural genetic differences tied to muscle strength and fitness influence depression risk.

Amy Taylor, PhD, co-author of the study and senior research fellow at University College London, explains:

"Because these genetic differences are randomly assigned at birth, the method helps overcome issues like confounding factors or reverse causality, which often make it hard to determine the real link between fitness and mental health."

The study focused on two types of genetic markers: one associated with cardiorespiratory fitness and the other linked to grip strength, which served as a proxy for overall muscle strength. Depression was assessed using hospital records, self-reported histories, and questionnaires evaluating specific depressive symptoms.

Grip Strength and Depression

The analysis revealed a clear association between higher grip strength and lower depression risk. Every 0.1 kilogram increase in grip strength per kilogram of body weight corresponded to an estimated 14% lower likelihood of developing depression.

Higher grip strength was also linked to a reduction in several common symptoms of depression, including a decreased inability to experience pleasure, more stable appetite, improved mood, lower levels of extreme fatigue, and better focus and concentration.

These results suggest that muscle strength may serve as a protective factor for mental health, particularly against symptoms that can limit daily functioning and overall well-being.

Women Show Stronger Benefits

One of the study’s notable findings is the difference between men and women. Taylor notes,
"We observed clear differences between women and men in how muscle strength relates to depression symptoms."

For women, an increase in grip strength of 0.1 kilograms per kilogram of body weight was linked to:

33% lower risk of an inability to experience pleasure
30% lower risk of depressed mood
26% lower risk of trouble concentrating

For men, the link was less pronounced, suggesting that women may gain unique mental health benefits from increasing muscle strength.

Why Muscle Strength Helps

The mechanisms behind the link between strength and mental health are still being explored. Michael Brustein, PsyD, a clinical psychologist in New York City, points out that:

"Cardio often tests endurance—the ability to push through. Strength is about agency—the ability to exert force. For someone experiencing the paralysis of depression, the immediate feedback of lifting a heavy object provides a sense of capability that walking or running cannot."

Strength may also serve as a biological buffer, helping to counteract fatigue and a lack of pleasure in daily activities. While cardio has social and cognitive benefits, strength training offers tactile, measurable results that can reinforce a sense of competence and control.

Amy Taylor adds that the limited effect of cardio in this study doesn’t contradict previous research linking aerobic fitness with mental health. She suggests that other factors, such as social interaction during cardio or reverse causation (depression reducing activity levels), may influence previous findings.

Integrating Strength Training and Cardio

Freepik | ArthurHidden | Women can support mental and physical health with simple weekly strength workouts and regular light cardio.

The study reinforces that both strength and cardio have a place in a balanced fitness routine. Thea Gallagher, PsyD, clinical associate professor of psychology at NYU Langone Health, notes:

"Cardio still provides mental health benefits, including reducing rumination and offering social support if done in groups."

Resistance training, however, should be considered essential for mental well-being. Experts recommend two to three sessions per week to maintain neurological and psychological benefits. These sessions don’t require bodybuilding-level intensity—focused lifting that challenges muscles can be sufficient to improve mood and resilience.

Practical Recommendations

For individuals looking to enhance mental health through physical activity, the study highlights several key strategies:

1. Include resistance training at least twice a week. Focus on compound movements like squats, deadlifts, and presses, or functional exercises that engage multiple muscle groups.
2. Maintain regular cardio to support heart health, energy levels, and social engagement.
3. Monitor progress with measurable strength markers, such as grip strength or lifting capacity, to stay motivated.
4. Pay attention to mental health symptoms and adjust activity levels to avoid overtraining or burnout.

This research adds a fresh perspective to the conversation about exercise and mental health.

Muscle strength may offer a protective edge, particularly for women, in reducing the risk of depression and its associated symptoms. Incorporating resistance training alongside cardio supports overall health, enhances mood, boosts energy, and builds a sense of capability.

By combining strength training with other forms of exercise, individuals can cultivate both physical resilience and mental clarity, reinforcing the idea that feeling strong is about more than just the body—it’s about supporting the mind too.