Any activity can burn some calories, but just burning calories does not necessarily translate to improved fitness or fat loss. Performing appropriately challenging workouts that stimulate positive changes in your body is the key to an effective exercise program. Well-designed cardio or resistance training workouts are the best way to achieve your goals, but common activities, such as cutting the grass, can be made into effective workouts.
Admittedly, grass cutting can be fairly strenuous (assuming you do not use a riding mower) and it may already be challenging enough to be considered exercise. Still, if you mow your lawn regularly, chances are your body has become somewhat used to the activity and it may not provide enough of a stimulus for positive change. You will have to use your best judgment to decide if you think it is too easy.
If you need more of a challenge, it is very simple to change grass cutting from a calorie burning activity into a fitness improving exercise. All you need to do is start timing yourself when you cut your grass. Assuming you are cutting the same size area each time and the weather is not drastically different, your goal should to finish a little quicker than the last time you cut the grass.
Most people cut their grass at a pace that is moderately fatiguing, but not really challenging, especially if they are in good shape. By having the intention to finish sooner, you will naturally move faster, which will significantly increase the challenge of the activity. Instead of your muscles just going through the motions, they will be pushing harder, similar to what happens during a challenging workout.
From an exercise standpoint, making this change is similar to increasing the speed or raising the incline on a treadmill. The end result is an increase in exercise intensity, which makes you work harder, and ultimately stimulates greater fitness and fat loss improvements.
Always remember the real goal is to increase your speed to the point where you are appropriately challenged, but not to the point where you struggle excessively. If you push yourself too hard, cutting the grass can be potentially dangerous and you could twist an ankle or experience some other injury. Just be responsible and use your best judgment.
It is also important to take the weather into consideration when cutting the grass or doing other exercise outside. Be sure to stay well-hydrated to prevent dehydration and if it is really hot and humid, don’t push yourself quite as hard as if the weather is nice and comfortable.
Finally, you still want to do a good job cutting the grass and if challenging yourself means you have to push yourself to the point where the lawn suffers, then you should probably just cut the grass normally and perform a more challenging workout at a later time.