Here is a 2 for 1 workout for you, combining a lunge and a chest.
How to: Start off in a standing position with your arms at shoulder height holding your resistance band (keep your elbows up) and take one leg back (as this will be the leg we will be the lunging leg).
Keeping your body upright, lower your knee towards the floor as you pull resistance band (almost like opening curtains!) and slowly return to the starting position.
Now you: Perform 3 sets of 12-15 repetitions on each leg. The resistance band is optional, so you can choose to leave it out or use dumbells. Too easy? Add a jump at the end of the lunge.