Calf raises

The Calf Raise is an exercise for the calf muscles.All the load of the calf raise exercise falls on the calves. You can perform it while standing, with a barbell, dumbbells or use a machine. During the exercise your heels should be in the air so you can move them freely.

This exercise puts works all muscles in the calves. The most important ones are the gastrocnemius muscles(forming the bulk of the mass of the calves) and the soleus (located below). Since exercise is isolated, it does work other muscle groups.The load on the calves depends on the position of the body.

The standing variation puts more load on the gastrocnemius muscles, and the seated option targets the soleus muscles.

Variations

• With barbell - Using barbell is a good choice if you do not have a machine available (Calf machine). The barbell can be placed on both the shoulders and in front of the body(in front of the stomach). 
• With Dumbbells - Dumbbells are more often for training each individual calf. The exercise is most often performed by bending one leg at the knee and holding a dumbbell with the hand which is on the same side as the bend leg , the athlete raises the other leg standing on his fingers. You can also put a weight on your quads and perform the exercise seated.
• Machine - The recommended variation of the exercise. Using a calf raise machine. The calf-raise machine puts all the load on the calves without employing any other muscle groups (such as the shoulders for added balance).
• Standing /Seated - The difference between them is that in the seated option you are removing the spine from the exercise but you are putting more load on the soleus.While standing, the spine participates much more actively, so you might consider using a lifting belt.
• Depending on the position of the feet - if feet are parralel the load of the exercise is falls on the whole calf muscle. Upon dissolution of the heel, the emphasis is changing and going more towards the inner head. Upon retraction   -emphasis on the outer head.

Method of execution

Preparation

1. Stand comfortably on the device (if using barbell or dumbbell, use the "wick" for better grip).
2. If you are performing the standing variation, it is recommended to use a lifting belt.

Execution

1. Raise heels by extending ankles as high as possible. Lower heels by bending ankles until calves are stretched. Repeat.

Tips for better performance

• Perform the calf raises with a moderate speed, but not too fast. You can injure your leg, so be careful. 
• Try to perform the movement in its full range of motion, but do not overdo it. Do not go too low. Stretching is a good thing but don't hyperextend.Once you feel a painless stretch in your calves, start the next rep.
• While performing the exercise keep your body straight and upright, do not bend your spine. Otherwise, it will put an unnecesary load on the spine and even carries an unpleasant risk of being injured.
• If you are using a barbell while performing the seated variation do not put the bar directly on your knees. It can traumatize them, especially if it's a heavy. Place the barbell slightly above the knee, but not too high so it doesn't lose its effect. Consider putting something soft under the bar if it's causing any pain.
• Warm up before performing the exercise do not start with heavy weight. The calf muscles are small, so you can easily hyperextend and hurt them.Warm up with a few sets with light weight and heavy repetitions.

Relevancy

Calf raises are a very good exercise for mass and strength of the calves.You can include it into your workout, regardless of experience level. If you are a beginner it's not mandatory to perform this exercise but when you progress, you will need to perform if you want to have bulky calves.

Perform it after the compound leg exercises(squats,deadlifts et cetera)If you are a beginner you should perform the calf raises at the very end of your leg workout.
(sources:exrx.net)
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