If you think that the only way to exercise and burn calories involves gym equipment, think again. Yard work can be just as challenging as a thorough aerobics workout at a nearby fitness club. To reap the greatest benefits, gardeners should use as little motorized machinery as possible. Manual tools will get you moving and can burn a substantial amount of calories. Try to vary positions and alternate which hands you use to reduce strain and get an even workout. Fitness experts say that gardening can improve strength, increase endurance and assist with flexibility. According to a report in the UK publication The Telegraph, clearing a pond or weeding can burn some 300 calories in an hour. Forty-five minutes worth of gardening can burn as many calories as 30 minutes of aerobics.