Playing soccer can give your body an intense workout, especially your legs. Soccer involves a lot of running -- much of it sprinting. This, combined with the repetitive kicking of the ball, can put your leg muscles -- particularly the quadriceps and hamstrings -- through a rigorous endurance and strength-training test. Whether you develop noticeably thicker thighs depends on how often you play soccer and perform weightlifting exercises.
Why You Need Strong Legs
Soccer tests your endurance and strength for 90 minutes. During the course of a match, your legs must have enough energy to be able to sprint at a moment's notice, while also dribbling, passing or shooting the ball. Performing these actions at late moments in a match, when your energy levels have been nearly depleted, requires conditioning and strength endurance. Playing soccer on its own can help you develop strong legs, but most competitive soccer players regularly lift weights as well to further strengthen their leg muscles.
The Quads and Hammies
Even though your entire body is engaged when playing soccer, the legs do most of the work. Developing defined and larger thighs is possible if you play soccer regularly. Soccer players must be able to run and sprint, control the ball with their feet and legs while running, accurately pass to teammates who may be as much as 60 yards away, and target shots on goal that travel at high speeds. All of these maneuvers and movements call your thighs into action, namely the quadriceps and hamstring muscles. The stronger your muscles are, the more effectively you can execute these types of soccer skills.
To the Weight Room
To build thicker thighs, incorporate regular strength training into your schedule. Aim to lift weights three times a week, and though you shouldn't ignore your upper body, focus on performing at least three leg-specific exercises during each workout session. Effective mass-building exercises for the thighs include squats, leg extensions, lunges, hack squats, leg presses and leg curls. If you are focusing on developing mass, limit the amount of repetitions and increase the weight for each set. Ideally, your leg muscles should reach complete failure at the end of every set.
... and on the Field
Soccer conditioning drills, combined with strength training, contribute to the development of large thighs. These include high skips, cariocas, backpedalling, sideways shuffles, heel kicks and knee-ups. All of these drills mimic, to a certain degree, movements you perform during a match, and complement any strength-training program you take up.