Fitness expert says 20 minute exercise is perfect for autumn health boostSports scientist Joanna Hall says it is the cheapest way to stay fit this seasonView Image Joanna HallA fitness expert says a simple, free exercise most people can do is an ideal way tio boost your health and wellbeing this autumn. Joanna Hall, sports scientist and creator of WalkActive said: “Autumn is the perfect time to reset your fitness because cooler weather makes walking more comfortable and mood-boosting. A brisk 20-minute walk can lift your heart rate, strengthen your posture, and clear your head. She said: “Walking outdoors doesn’t just get your steps in, it wakes up your body and mind. “You can walk on your commute, at lunchtime, or even while catching up with a friend,” she said.