These workouts come from talking to several personal trainers and pro skaters, my own experience, and working on an article for Men's Health magazine about skateboarder work out routines. Now you get the info, free!
1. Skateboarder Work Out Routine - Calf Raises
Find a block of wood, or a step, and standing with just your toes on the edge and your heels hanging over the side (check out the picture to see what I mean). Raise yourself up on your toes as high as you can, and then slowly lower yourself until your heels hang as far down as you can let them go. Do this 10 to 20 times, rest for a minute or so, then do it again. Then one more time, for 3 sets total.
If you've never done this before, you probably won't feel sore right then, but the next day you might be really stiff! If so, do it some more!
As you get stronger, you can hold wights while you do your calf raises. Gyms will often have a machine that you can use.
2. Skateboarder Work Out Routine - Leg Press
For leg presses, you're going to need to use a leg press machine. Sit in it, like in the picture to the side. Put your feet up on the foot plate with your feet about shoulder-width apart. Adjust the plate so that your knees are bent at about a 90 degree angle. Set the weight at a light level, something like 10 or 20 pounds. Then push and straighten your legs, but don't lock your knees. Do this a few times, and see how tough it is. Adjust the weight, and do more. You want to get to the point that doing 15 in a row is tiring, but doesn't hurt. Then do two more sets of 15.
3. Skateboarder Work Out Routine - Leg Extensions
You'll need a machine like the one in the photo. Sit in it, and lock your ankles behind the pads. For leg extensions, you kick your feet up until your legs are straight. Adjust the weight the same way you did for the leg press - start with a small amount, and work up until you have a good idea of how much to do. Again, your goal is 3 sets of 15 repetitions.
With all of these weight training exercises, you can do higher weight and fewer repetitions, if you want to build strength only. Doing 15 reps helps build endurance, which is usually what you want for skating.
4. Skateboarder Work Out Routine - Crunches
For crunches, lay on your back, knees bent, with your hands behind your head (just like you were about to do situps, but without anyone holding your feet down). Then pull up your head and your feet, touching your elbows to your knees, flexing tightly, and then relaxing back again. Do 15 or 20, rest, then do two more sets of the same.
There are often several machines you can use at gyms. If you are already at a gym for the other workouts, check and see if there's a machine for abs for you to use.
5. Skateboarder Work Out Routine - Stretching and Excercise
Stretch out each body part that you've exercised, holding the stretch for about 30 seconds. Bending to touch your toes, pulling your feet one at a time back toward your butt, and stretching your legs apart as wide as you can are all good stretches.
For exercise, things like riding a bike (outside, or a stationary bike at the gym), jogging or swimming are all great. Doing any of these will give you more strength and endurance for skateboarding. And vice versa!
For more details, check out Skateboarding Stretches and Exercise.