Lorraine,
Here is the universal way to lose weight and tighten up:
1. Continue doing what you've been doing with the resistance machines. Use enough weights to be able to do 6 - 10 reps but no more. For abs, add planks to your captain's chair (which I am not familiar with).
2. Progressively add more cardio. 4 miles on the stationary bike is not very far. Add running if you like. Cardio 3x / week is what the American Heart Association recommends but many on here, like me, do it 4, 5, or 6 days / week.
3. Determine your basal metabolic needs.
Basal Metabolic Rate & Calories Burned Daily Calculator and ratchet down the intake, i.e. food, to "tighten up". 1 pound of fat requires a deficit of 3500 Kcal, so if you shoot for a deficit of 500 kcal / day, that will allow you to lose 1 pound / week. Your waist will thin out and you will feel less soft as the underlying muscles become closer to the surface.
And don't use age as an excuse! I am 49, a two-time cardiac patient (including open heart surgery on April 4) and am doing my first sprint triathlon a week from today and preparing for an Ironman late this year or next year.