Located on the lower back portion of your leg, the calf muscles extend on the top part of the leg. Their development depends upon the activities you perform in your daily life and focused exercises you perform to enhance them. Their physiological makeup can provide some clues as to why they can be large and highly developed in some people.
Your calf muscles consist of two chief muscles. The outermost muscle is the gastrocnemius. This muscle begins just behind the knee, yet splits into two portions, according to Fit Step, a muscle health and wellness guide. If you have extremely muscular calf muscles, the gastrocnemius may appear diamond-shaped. Situated just beneath this muscle is the soleus muscle. This muscle gives the calf its shape and works when you are performing calf exercises when seated, such as seated calf raises.
Your calves are responsible for a number of functions related to your daily life --- when you lift up on the balls of your feet to reach a top shelf, climb the stairs or move your leg to kick a soccer ball, you are using your calf muscles, according to Get Body Smart. For this reason, calf muscles can be very developed or large in those that are very active or who do a lot of reaching or stair climbing on a daily basis. Because you have two muscles over each other that essentially perform the same function, an exercise that works one typically works the other --- this builds muscle size.
Calf muscle size often depends upon relative leg size, genetic history and the activities you perform. For example, some people may have larger thighs and calves with little muscle tone --- a condition known as "chicken legs"--- while others have large, developed calves and little muscle tone in the legs, according to Shape Fit. The key then becomes proportional balance in order to ensure the calves are proportional with the rest of the body.
To reduce large calf muscles, try increasing the amount of reps you use on calf exercises while decreasing weight --- this helps to slim the legs, according to Calf Reduction, a health and wellness site dedicated to toning the calves. Stretching programs also can help to reduce calf size. If your calves are not large enough, seated and standing calf raises can help, according to Shape Fit.
In some instances, large calves can be signs of a more serious condition, according to the American Academy of Family Physicians. If your calves or just one calf seems swollen, red or warm to the touch, your large calf muscle could be due to an obstruction of the veins, which is known as deep vein thrombosis. This is a very dangerous condition that can lead to stroke if not diagnosed. Seek a physician's evaluation if your large calf muscle could be due to this or another medical condition.