By now we all know the health benefits of exercise and how it increases our fitness and longevity. But a leading expert explores the psychological and emotional aspects of exercise, especially those group workouts that connect us with others.

"People who are physically active are happier and more satisfied with their lives," says Kelly McGonigal, author of "The Joy of Movement: How Exercise Helps Us Find Happiness, Hope, Connection, and Courage."

"They have a stronger sense of purpose, feel more gratitude, are more connected to their communities, and are less likely to feel lonely or anxious."

McGonigal is a health psychologist who specializes in understanding the mind-body connection. Here are five ways she says exercise impacts the brain:

1. The exercise "high" helps you connect with others. That almost euphoric feeling experienced by runners can be enjoyed by those participating in any sustained activity — even dancing. Research shows that exercise releases brain chemicals called endocannabinoids, the same class of chemicals mimicked by cannabis, which reduce anxiety and create a state of contentment.
2. Exercise makes your brain more sensitive to joy. Regular exercise increases the levels of dopamine in the brain, relieving depression and expanding your capacity for joy. "Since adults lose up to 13% of the dopamine receptors with each passing decade, physical activity can prevent that decline," says McGonigal.
3. Exercise make you brave. The expert says that regular physical activity calms the "flight, fight, or fright" response of the brain and balances your nervous system. It also helps you develop a sense of pride and courage as you learn to perform certain movements. You build confidence in your ability to overcome obstacles.
4. Moving with others builds trust and belonging. One of the chief traits of people who live in the Blue Zones, areas around the world where longevity and good health thrive, is that they work and pray together. "Individuals have described a feeling of euphoric self-transcendence when they move together in ritual, prayer, or work," says McGonigal. "Group exercise such as yoga, dance, or indoor cycling classes is one of the most powerful ways to experience this joy."
5. Trying a new activity transforms your self-image. "Any form of exercise can help you feel good about yourself," says the author. "If you want to feel more graceful, try a dance class. If you want to feel more powerful, try strength training. To discover a new part of yourself, choose a movement that reflects the qualities you want to develop. And know you are not just strengthening your heart and your muscles. You are also strengthening your capacity to experience happiness, connection, and courage."

Heather Gunn Rivera, co-founder of "Grass Roots Fitness Project," tells Newsmax that getting started isn't complicated.

"Just find a way to move and move consistently — every day if possible," she says. "And do it with community. Surround yourself with people who reflect who you want to be and how you want to feel. Positive energy is contagious!"