When you're trying to get stronger legs for bicycling, there's one main thing you should be doing -- bicycling as much as you can. To strengthen the muscles used during the activity, you have to actually do that activity. However, you also have some other options for helping you gain muscle when you're not in the saddle.
Before you set out to build the muscles used in cycling, it helps to know which ones to focus on. Bicycling primarily uses the hamstrings at the back of the thighs and the quadriceps at the front of the thighs. Additionally, the muscles of your calf, including the gastrocnemius and soleus get into the action. On top of that, it helps to have a strong core, as it's the foundation of movement for the rest of your body. The core includes the abdominal muscles at the front and sides of your torso, as well as your chest, shoulders and back. Set a schedule that allows you to do muscle-strengthening exercises two or three days a week on non-consecutive days, giving your muscles time to rest and recover between sessions.
Many of your options for strengthening your legs and core are exercises you can do in your own living room. Start out doing a set of squats to work the quadriceps, hamstrings and butt. Keep your feet slightly wider than shoulder-width apart, and then bend your knees and lower your butt as if you're going to sit in a chair. Also do lunges by standing with your feet a few inches apart, and then step forward with one leg, lowering the back leg's knee to close to the floor. Step back to standing and then repeat the movement with the opposite leg. Also try calf raises to work the gastrocnemius and soleus. Stand near a wall, hold one foot behind the opposite knee and then stand up on tip toe with the standing foot. For each of these exercises, do 12 to 15 repetitions, take a short break and then do a second set. For the core, do pushups or hold a plank position for 30 seconds or more. Planks involve holding the "up" position of a pushup.
Training at the Gym
Exercises in the weight room can also help you gain strength -- and since they're forcing your muscles to work with added resistance, you may see results faster than you would if you only did the body weight exercises described above. Choose the sled press or the barbell squat for the quadriceps and hamstrings. If you're not sure how to use those machines, get help from a trainer or coach at the gym. Lunges holding a barbell are also effective for the quadriceps, hamstrings and glutes. To strengthen the hip flexors, which also contribute to strong cycling, use a stationary bicycle at the gym and cycle with one leg at a time, recommends USA Cycling coach David Ertl, Ph.D. For the core, do a set of pullups or use the assisted pullup machine that displaces some of your weight and helps you gain confidence with this difficult yet effective exercise.
Getting stronger involves building more muscle mass. Cycling as often as you can -- whether it's indoors or out or in a spinning class -- is going to help you build strength, and the strength training you're doing will help you build it faster. On top of that, don't overlook the importance of eating adequate amounts of protein, the building blocks of muscle. The average person needs between .4 and .5 grams of protein per pound of body weight per day, says the American Council on Exercise. Timing your protein intake and eating certain types of protein will help you gain muscle faster. Try eating an energy bar or drinking a shake containing casein, found in milk, before your workout, which will provide you with a slow-release form of protein. Following the workout, consume another bar or shake containing whey, which is a rapidly-available type of protein that will help build muscle immediately following your workout.