Workout challenge do intervals with your cardio instead of going the same pace for a longer duration sometime this weekend. Do a 5-10 warm up. Then do 10-15 rounds of 30 sec of a very intense pace followed by 1-2 min of a lower pace as recovery. Then a xo down of 5-10 min. This can be done on the treadmill, bike, elliptical or even during an outdoor run.