Congrats on turning a new leaf! Honestly, you're never too old to get in shape but no one wants to spend years being unhealthy when they could be feeling great, looking great and in great health. The elliptical will definitely help you burn more calories which will help with the weight loss but in order to increase and/maintain your muscle you should be adding resistance into your workout. Any program that lacks resistance will yield a loss of 40% muscle. That means if you lose 10 it is likely that 4 lbs of that 10 is muscle. If you lose that muscle you loose your metabolism. The resistance helps to keep the muscle constantly rebuilding so that even if your body is trying to use muscle, you are fighting it. Loss of muscle mass is also ultimately what sends folks to retirement homes as well. As you age you will gradually lose muscle (unless you do resistance to fight the loss) and it will begin to limit your ability to do the once simple tasks of daily life. I hope this helps! Good luck