I practiced some art martials and combattive sports, sometimes to have energy, some times for self defense.
Each have is own advantages over others, it depends on what you really seek.
On of them can be practiced by anyone, it's Tai Chi.
The advantage, is that you can practice it at any age, and it brings a lot to you.
When you have a buzzy life, or if you have some pressure at work for example, and any other case when you feel low in energy and in yourself, Tai Chi can bring you back to your roots.
It helps you re taking your body control and breath , because during the day at work if it's an intellectual work, or stressing work, you loose yourself and your breath.
Tai Chi , will progressively make you more relaxed, specially during movement exercice where you'll try to keep a relaxed breath and body during the effort could it be light.
You'll work on your intern inner energy and develop it as you practice regulary ,if you can and make the effort to keep some regularity. And you'll develop also some natural patience against all the daylife situations where you have to wait could it when you go eating at lunch time, or any other situations.
So i really encourage people having some static work , that lot of time is not so good for body to practice Tai Chi exercices to regain a more natural energy , breath and movement.
Some random links : (nothing reaplace a real lesson)
other random sites :