Slacking on exercise.
You DO have enough time to exercise. If you say otherwise, you're lying to yourself. The truth is you don't have time not to,or sooner or later you'll be making time for illness.
At least 30 minutes of exercise every day has been proven on countless occasions by countless medical studies to increase the strength, happiness and longevity of human lives.
You're talking about three and a half hours a week.That's hardly seems an excessive amount of time considering the tremendous benefits in terms of the impact on the remaining 164.5 hours of the week.