You can do exercises sitting down.
You can do exercises standing up.
If overall functional ability is a goal, you’d like to get more done quickly, and you have a choice between the two, stand up. Here’s why.
When you exercise sitting or lying down, you engage fewer muscles. Think about it. You’ve got a machine or bench to brace yourself against. For example, do a standard bench press and your body is braced by the bench. The primary muscles of the chest do the work, but the rest of your body isn’t engaged. Recruit more muscle, you get more done.
If your fitness center has a cable machine (one of the best pieces of strength equipment you’ll find in the gym, by the way, so if your gym doesn’t have one, ask them why not and when they’re getting one), stand up and do a chest press using the cable machine. Your lower body has to engage to keep you standing. Your core has to engage to keep you upright. The stabilizing muscles of the body are firing as you’re performing the exercise and managing the independent movement of each cable and the constant tension of the cable machine.
If you’re looking for functional strength, this exercise will simulate normal movement more effectively. For example, most peopleI rarely find themselves lying down with a heavy weight on their chest and needing to lift it up. However, have you ever found yourself pushing a heavy shopping cart? The standard barbell chest press is more like the first scenario. The standing chest press is more like a normal movement.
If weight loss is a goal, standing exercises engage more muscle which means you use more calories. When it comes down to it, using more calories than you take in is the name of the game.
Go ahead, stand up! Here’s a video to get you started.