Although Tremaine is correct about walking, some of us like to run. I run 5k, stretch out, and then work out at the gym. I dream of running when I'm sleeping. And I live most of my life in cities where it is more convenient to walk everywhere and very inconvenient to own an automobile. Best of both worlds.
As for running, there is one thing about which I have firm (pun intended) evidence. If I quit running for several months my lower butt cheeks begin to sag. Running requires that I use a complete range of motion, especially from my stomach to my toes, as I keep my posture aligned to deal with the stress of the activity. Walking . . . well, power walking, requires the same range of motion. But how many of us are constantly aware of our posture when we walk? I was off my running schedule while recovering from knee surgery last year (not related to running). However, I still walked everywhere. The Squeeze took before and after photos of my ass. Off my running schedule for three months made me look like I've got a 65 year-old skinny wrinkled ass. Since I've been back to running 5K (not everyday, but most days . . . because I like it) I have a 65 year-old bubble butt that looks like it belongs to a gym rat in his mid 30s.
Of course, what you eat affects dramatically how you look. Don't overlook that aspect of staying healthy.
So, if you're young and within the physical norm for your body type, you should notice the same effect as a gentle butt lift. As for calves, from what I've seen people without major calves eventually get them from doing the correct series of exercises.
Shin splint tip: If you begin to develop shin splints (which are little scars in the smooth muscles covering your shins because you've damaged them from not doing what you can to stretch them before or after running), here's some advice that I received from an ancient ballet instructor who I swear was really an evil witch who ate little children. Well, maybe she didn't eat them, but she was never more happy than when she made them cry in ballet class.
Take 25 pennies (or similar size coin).
Toss them on the floor.
Pick up each coin using only the toes on your right food, placing each one in your hand.
Repeat steps 1 through 3 for the left foot.
Try to do this twice a day.
It works. It really does. You can do it while your watching TV.