Want to double your exercise without doubling your time doing it?
When you walk with a walking stick in each hand (and use it), you are doubling your calorie burn and developing upper body strength. The motion simulates the motion that occurs in cross-country skiing, the all time best calorie burner around. If you think people will laugh at you, put out the word that you are training for delivering relief supplies to remote areas of any country that has cold and snow. That should turn derision into wonder (nothing like a little shame) and you can work out in peace.