For some, the burn of muscles under vigorous use is a positive sensation — confirmation that you're working out hard. But if you feel pain in your hamstrings when cycling, stop what you're doing and consider the cause: That pain might signal an injury or a problem with your posture.
Hamstring pain while cycling can come from several causes, including an acute muscle strain, improper seat height, the wrong frame geometry for your body and cycling goals, or hamstrings that are too tight or too weak.
Muscle Strains Are a Possibility
Any time you feel a sharp pain in a muscle, a strain — aka a pulled muscle — is a real possibility. Muscle strains are graded by severity, with a mild grade-one strain usually healing readily with home treatment, while a grade-three strain is a completely torn muscle or avulsion, as illustrated by the American Academy of Orthopaedic Surgeons' OrthoInfo.
As the AAOS notes, hamstring strains are often caused by large, sudden loads — such as shifting suddenly from moderate cycling to a sprint. Other risk factors include tight muscles, muscle fatigue, generally deconditioned muscles, or muscular imbalances that lead one muscle group to fatigue too quickly — a common issue with hamstrings, which are often weaker than they should be in relation to your quadriceps, the opposing muscle group at the front of your thighs.
The symptoms of your muscle strain may include a sudden, sharp pain; muscle spasms; bruising or discoloration; persistent weakness or limited range of motion in the affected muscle; or swelling within the first few hours of your injury. In case of a serious strain, you might even hear a pop, lose function in the affected muscle or notice that the shape of the muscle is visibly different.
Caring for a Strained Hamstring
If you've suffered a serious muscle strain while cycling, stop and get to a doctor. If you've suffered a mild strain, you can probably treat it at home, as the Mayo Clinic points out. But take it as easy as you can on the way home, or get someone to come pick you up if at all possible.
The typical home care for a muscle strain is RICE (rest, ice, compression and elevation), although the Mayo Clinic notes that you should see a doctor if your symptoms worsen, if your pain is intolerable, or if you experience the symptoms of numbness or tingling. In the case of a severe tear, you might need surgery or physical therapy to rehabilitate your injured hamstring.
Read more: Is Cycling Good for the Knees?
Is Your Seat Too High?
There's another hazard, totally unique to cycling, that could cause your hamstring pain: As noted in a systematic review published in the December 2017 issue of the International Journal of Sports Physical Therapy, having an excessively high saddle can contribute to chronic overload of the hamstring muscles and tendons.
You might also notice calf pain when your bike saddle is too high, as the too-high seat forces you to constantly "reach" for the pedals. You might also notice your knees locking out or your hips rocking side to side as you pedal on a bike seat that's adjusted too high.
If you're not sure how to adjust your bike, a professional bike shop can help. If you've never had the benefit of an expert bike fitting, it might be a true revelation that improves several aspects of your riding experience. It's especially helpful if you're purchasing a bike for the first time, because the bike frame's geometry — and in particular, the angle of the seat post — can affect your hamstrings.
For example, an analysis of bike geometry published in the March 2006 issue of the Journal of Sports Science and Medicine noted that a triathlon bike frame, which places the seat at a farther forward angle, can help to reduce hamstring tightness.
However, that aggressive forward lean might not be ideal for recreational bikers. Having a seat that's set too far back can also cause hamstring problems. Again, a professional bike fitting is your best bet for getting the right geometry for your biking purposes and your body.
If you're on your own, there are several methods for gauging the appropriate height of your bike seat. Brookhaven National Laboratory recommends sitting in the saddle, placing your foot in the pedal and moving that foot to the downward limit of the pedal stroke. In that position, your knee angle should be between 25 and 35 degrees; they note that for most riders, a 25-degree bend is ideal. Don't overcorrect — having your seat too low puts too much force on your knees and can cause other problems.
Still not sold on the idea of a professional bike fitting? A good bike shop will look at all aspects of your cycling posture, including how much weight you're placing on your hands (and the handlebars); the forward lean of your body, which, in turn, can affect your neck and shoulders; where your hands fall on the handlebars themselves; and how well your feet (or the cleats of your cycling shoes, if you have them) line up with the pedal crank arm.
Read more: 11 Amazing Benefits of Biking
Other Reasons for Hamstring Pain
There's another reason you might experience hamstring pain, although it's not exclusive to cycling — muscles that are too tight or too weak can end up hurting too.
If you need to strengthen your hamstrings, isolation exercises like the leg curl can help — but you also need to strengthen them through movement that integrates your own muscle groups, because that's how your body works in the real world. According to research sponsored and published by the American Council on Exercise, the best exercises for activating the hamstrings include kettlebell swings, reverse hip raises, the fiendishly difficult glute-ham raise, and single arm/leg Romanian deadlifts.
Finally, although flexibility is often overlooked as a component of fitness, taking the time to stretch after your workouts is an easy, no-stress way to increase your range of motion and loosen up tight muscles, which can then reduce your risk of injury.
Consider incorporating either (or both) of these simple hamstring stretches at the end of your workouts:
Move 1: Seated Hamstring Stretch
Sit sideways on a weight bench, park bench —
or even the edge of your bed if it's firm enough.
Extend the leg that's on the bench/bed straight; keep the leg that's not on the bench planted on the floor for stability.
Maintain a straight back as you hinge forward from the hips, leaning slowly forward until you feel tension in the hamstrings of your straight leg.
Hold the stretch at the point of tension — not pain — for 30 seconds, and repeat a total of three to five times. Then stretch your other leg.
Move 2: Lying Hamstring Stretch
- Lie face-up on an exercise mat, the floor or your bed. Bend both knees and plant your feet.
- Straighten your right leg, and slowly bring it up — your goal is for it to point straight up, or as close as you can get it while keeping your leg straight.
- Gently draw back on that thigh, if necessary, to create tension in the hamstring of the straight leg.
- Hold the stretch at the point of tension for 30 seconds, and repeat for a total of three to five times. Again, stretch the other leg next.
- Ohio State University: "Common Issues Affecting Cyclists"
- Brookhaven National Laboratory: "Common Overuse Injuries Attributed to Cycling, and Ways to Minimize These Injuries"
- International Journal of Sports Physical Therapy: "The Influence of Extrinsic Factors on Knee Biomechanics During Cycling: A Systematic Review of the Literature"
- Journal of Sports Science and Medicine: "The Effects of Bicycle Frame Geometry on Muscle Activation and Power During a Wingate Anaerobic Test"
- American Academy of Orthopaedic Surgeons: "Hamstring Muscle Injuries"
- ExRx.net: Common Muscular Weaknesses
- Mayo Clinic: "Muscle Strains"
- Hospital for Special Surgery: "Does Your Bike Fit You?"
- American Council on Exercise: "ACE-Sponsored Research: What Is the Best Exercise for the Hamstrings?"