For instance, the wood chop exercise where you reach up with a weight and then down to the opposite side will help you (not only to chop wood) but when you are reaching up and getting items out of overhead cabinets in the kitchen or putting a suitcase up in the overhead bin.
Functional training is great for senior citizens. It helps strengthen the muscles they need to do their daily activities. I asked one of my senior clients (she is 83, by the way) why she exercised. She said "If I don't get up and move, I will not be able to get up and move."
In functional training you can use dumbbell weights or resistance tubing to give you the resistance you need to build the muscles for that activity. The benefit of this type of training is that you are working multiple muscles at the same time and not isolating muscles. This way your workouts can be shortened to fit in the ½ time frame and you will notice the difference in your daily life.
Doing exercises to strengthen your lower back makes you stronger so you can pick up the grocery bags or pick up your grandchildren. Strengthen your upper body helps you pull yourself up off the floor or out of the tub.