How Your Dog’s Physical Fitness Affects Their Behavior

We usually think of fitness as something we build so our dogs can hike longer, run faster, or compete better. But strength, coordination, and balance reach far beyond performance. How a dog moves affects how they feel, how they handle stress, and how they respond to the world around them.

A stable body supports a stable mind. When dogs lack strength or awareness of where their body is in space, they can feel uncertain and off-balance. That unease often shows up as tension or overreaction. In human studies, proprioceptive activities—work that improves awareness of movement and body position—are linked to better emotional regulation and lower anxiety (McDonnell et al., 2015; Schaaf & Miller, 2005). We see similar patterns in dogs: as coordination improves, many dogs become more relaxed and focused.

Exercise also changes a dog’s internal chemistry. Regular, moderate physical activity lowers cortisol and boosts serotonin and dopamine, hormones that influence mood and attention (Hekman et al., 2012; Coppola et al., 2006). Dogs who move consistently and build fitness recover from stress more quickly and show fewer signs of anxiety or reactivity (Tiira et al., 2016). It’s not about exhausting them—it’s about creating a body and nervous system that can return to calm easily.

Pain is another piece of the puzzle. Many behavior issues trace back to discomfort that owners never notice. Chronic tension, muscle weakness, or minor orthopedic pain can make a dog short-tempered or touch-sensitive (Mills, 2020). Strengthening core and stabilizer muscles improves posture and comfort, which in turn reduces irritability and improves focus (Zink & Van Dyke, 2018; Lewis et al., 2020). When movement feels good, a dog’s behavior often changes with it.

Thoughtful movement also acts as enrichment. Balance work, careful footing on uneven surfaces, or slow, deliberate stepping over poles all build body awareness and calm (Wells, 2004; Nithianantharajah & Hannan, 2006). These exercises give dogs a sense of control over their bodies, and that confidence carries into everyday situations.

We talk a lot about training the mind, but training the body deserves equal attention. A fit, comfortable dog is better equipped to think, listen, and recover. If your dog seems anxious or reactive, try adding short sessions of structured movement and strength work. You may find that as their body steadies, their mind does too.