In case you were wondering how important it is to maintain your muscle as you age, take a look at this series of pictures:
The first one is the cross section of a 40 year old triathlete’s thigh. Note the solid fibers of muscle in the quads and hamstrings.
The 2nd picture is the thigh of a sedentary 74 year old man. All that white stuff is fat tissue that has infiltrated its way through the muscle. Note the lack of muscle integrity and even the smaller bone in the middle.
Now look at the 3rd picture. A 70 year old triathlete who has maintained muscle strength and activity looks almost identical to the 40 year old.
We tend to think of getting older as an inevitable decline into weakness and loss of function. I’m here to tell you that the weakness is optional. While you may not be a triathlete, what you should take from this example is that you either use it or you lose it. Our bodies are very efficient at allocating resources. Muscle that is not used eventually gets metabolized and broken down to save caloric requirements. But if you keep challenging them then our bodies decide that these muscles are worth keeping around and maintain them just as well as when we were younger. Age doesn’t really matter.
Regular training can be the difference between living a quality life until you're elderly or living in a nursing home needing someone to wipe your butt for you.
And it doesn’t need to be a crazy amount of working out. Even a few exercises spread throughout the week can be enough stimulus for your muscles to realize that they are still needed and prevent their atrophy.
If you want to build or maintain some leg strength, give these Kickstand Squats a try. You can use just your body weight or hold an appropriate size dumbbell in front of you as you do it; scaling can always be done upward or downward.
The staggered position allows the front leg to take the majority of the load while the back foot provides balance and light assistance. Find a load that allows you to get 8-12 reps per set (trying to work up to a total of 20-30 repetitions), do these 2-3 times per week, and your legs can look more like that last picture in the long run.
The choice is yours.