Pain in the left side of the hip: causes and warning signs

Pain on the left side of the hip does not always start in the joint. Sometimes it begins in a tight muscle, in an irritated tendon, or in the lower back and slides toward the side like a stab that appears when walking, climbing stairs, or turning in bed. At other times, the source is higher up or lower down than the body seems to indicate: the colon, the kidney, or even the back can send the discomfort there.

For runners, that confusion is especially common. The hip absorbs repeated impact, changes of pace, hills, and trunk rotation, so a mild overload can seem like a major injury and, conversely, an internal problem can masquerade as a simple muscle strain. The key lies in how it hurts, when it hurts, and what else accompanies the pain: whether it appears with movement, worsens when taking a deep breath, radiates to the groin or the back, or comes with fever, nausea, or burning when urinating.

The left hip is not a single piece

Talking about the hip as if it were a single point leads to mistakes. In reality, the side of the pelvis concentrates muscles, tendons, bursae, nerves, the joint, the lower spine, and nearby abdominal structures. That is why a localized ache on that side can seem like a sports injury and yet be related to a digestive, kidney, or lower back problem. The territory is small; the causes are not.

The outer region of the hip is often involved when there is overload of the glutes, trochanter irritation, tension in the tensor fasciae latae, or inefficient running technique. By contrast, deep or more internal pain usually suggests the joint, sacroiliac joint, spine, or visceral structures. That distinction does not provide a diagnosis, but it does accurately guide the map of the problem.

Timing also matters. Pain that appears at the end of a long run, after intervals or hills, suggests accumulated mechanical load. Pain that wakes you at night, is accompanied by stiffness, and does not change much with movement deserves a different interpretation. And if the body adds fever, vomiting, dizziness, or urinary changes, the focus stops being athletic and becomes medical.

Mechanical causes usually lead the way

In practice, the most common explanation for lateral hip pain is mechanical. Muscle strains, muscle overuse, gluteal tendinopathy, and trochanteric bursitis are among the most frequent causes. The hip, like a hinge that never rests, withstands hundreds of thousands of repetitions each month. When the stabilizing muscles fatigue, the area protests with a dull or stabbing pain that worsens with weight bearing, running, or standing for long periods.

Bursitis appears when the bursa, that small sac that cushions friction between tissues, becomes inflamed. The result is usually pain on the side of the hip that bothers you when lying on that side, crossing your legs, or climbing one step after another. Gluteal tendinopathy, on the other hand, usually produces a more persistent sensation, with tenderness to pressure and gradual worsening during activity. In both cases, the body does not shout; it slowly turns up the volume.

The lower back can also play a role. Irritation of the lumbar area or the sacroiliac joint can refer pain to the left hip and make you think the injury is where only the echo is felt. In athletes and active people, this confusion is very common, especially if training has increased suddenly, if fatigue has built up, or if footwear and technique are not helping.

When the problem is not in the hip

The abdomen and urinary tract can also explain side pain in that area. The left kidney, the descending colon, and part of the digestive system are close enough for discomfort to be projected toward the side. A kidney stone usually causes very intense pain, sometimes in waves, which can radiate to the groin and be accompanied by nausea, cold sweat, or blood in the urine. It does not resemble the typical sports overload; it has its own pulse, rougher and harder to ignore.

Digestive disorders, such as gas, constipation, gastritis, or colon irritation, can produce a feeling of pressure or cramping on the left side of the abdomen that is confused with the hip. In these cases, the body usually changes the script with signs that do not belong to the musculoskeletal system: abdominal bloating, changes in bowel habits, nausea, or partial relief after a bowel movement. That combination matters more than the exact location of the pain.

There is another less common but important scenario: referred pain from nearby organs or from more serious inflammatory processes. The spleen, for example, can hurt in the upper left side if it becomes inflamed or is hit. Although it is not the most common cause, its presence calls for a broader view, because anatomy does not always respect our labels of hip, abdomen, or side.

Signs that help distinguish a sports-related cause from an internal one

The way pain feels provides valuable clues. Muscle or tendon pain usually worsens with certain specific movements, with direct pressure, or when loading weight onto the affected leg. It often improves somewhat with relative rest and becomes noticeable when starting off, turning, taking long strides, or standing up after sitting. When movement triggers it and rest calms it, suspicion usually points to mechanical structures.

By contrast, if the pain appears without any clear relationship to exertion, wakes you at night, or is accompanied by fever, vomiting, burning when urinating, shortness of breath, or general malaise, you should think of something else. Intensity matters too: sudden, very sharp, unusual pain deserves prompt attention, especially if it prevents normal walking or limits simple actions such as sitting, coughing, or taking a deep breath.

Fine location also speaks. Discomfort on the outer side often points to the trochanter, tendons, and stabilizing muscles; a deep sensation in the groin is more associated with the joint; posterior pain with the back or kidney. It is not a laboratory rule, but it is a useful compass for not navigating blindly.

What a professional usually finds when examining that area

A proper diagnosis is not based on a brief description alone. A clinical examination usually checks gait, hip mobility, glute and abdominal strength, sensation, the lumbar spine, and the response to weight bearing. The goal is to separate a muscle-related complaint from joint, nerve, or visceral pain. That difference completely changes the subsequent management.

If the picture suggests a muscle, tendon, or bursa injury, imaging tests such as ultrasound or MRI may be useful, depending on the case. If urinary or digestive symptoms appear, other tests are ordered, such as urine tests, blood work, or abdominal studies. In cases with warning signs, the priority is no longer to label the injury, but to rule out emergencies. The body does not always warn dramatically; sometimes it just gradually sharpens the discomfort.

It is also worth considering the context: age, recent loads, falls, a history of osteoarthritis, past kidney stones, previous digestive episodes, or changes in training. Hip pain in a runner who has increased volume and elevation gain is not interpreted the same way as pain in someone with fever, chills, and pain when urinating. Useful medicine starts by comparing.

What usually helps when the cause is musculoskeletal

When the problem is mechanical, relief usually comes through relative rest, a temporary reduction in impact, and load correction. The goal is not to immobilize, but to reduce pressure on the irritated tissue while inflammation settles. In many cases, a short break from running, combined with gentle activity such as walking or pain-free cycling, makes more sense than pushing through the discomfort.

Local heat can relax a muscle spasm; ice can soothe an inflamed area after exertion. The difference is not magic, but the phase of the process and the patient’s sensation. Movement hygiene also helps: avoid sleeping on the painful side, do not cross your legs if it worsens the discomfort, distribute loads better, and reduce hills, intervals, or explosive strides for a few days. Less punishment, more room for the tissue to breathe.

Physical therapy is often helpful when there is a clear component of overload, tendinopathy, or mechanical dysfunction. The work usually focuses on hip and pelvis mobility, trunk control, glute strength, and a structured progression of load. In running injuries, recovery depends not only on calming the pain, but on restoring the area’s ability to absorb impact.

When digestive or urinary causes completely change the approach

If the pain comes from the digestive system, treatment is no longer aimed at stretching or unloading the hip, but at resolving the specific cause. Significant constipation, gas buildup, or an intestinal inflammatory process may require dietary changes, hydration, medical treatment, or additional tests. Here, the painful area is misleading; the problem is on another level.

In kidney-related cases, the urgency can be different. A kidney stone does not get fixed with massages or a simple break from training. It is usually intense, very characteristic pain that can come in waves and move toward the groin. Fever, blood in the urine, chills, or unbearable pain require prompt medical evaluation, because there may be an infection or urinary obstruction.

Hydration alone does not cure everything, but it is part of preventing many urinary problems and maintaining proper digestive function. In runners who sweat a lot or train in hot weather, maintaining adequate fluid intake is a basic habit that is often underestimated. The body does not handle the desert well, neither on the track nor in the abdomen.

When pain means you should stop and seek medical advice

There are situations in which waiting is not a good idea. Very intense, sudden, or persistent pain, especially if it prevents normal walking, if it is accompanied by fever, vomiting, shortness of breath, dizziness, blood in the urine, or pain that strongly radiates to the back or groin, requires medical assessment. A pain that does not improve after several days of relative rest or keeps returning with minimal effort also deserves review.

In athletes, a stress fracture, a more serious tendon injury, or a joint problem may initially seem like a simple ache. However, if the pain increases with weight bearing, appears even at rest, or changes the way you walk, it should be taken seriously. The body compensates for a while, but not indefinitely. When gait changes, new problems often follow.

If the pain appeared after a fall, a direct blow, or an accident, caution should also increase. The hip is a robust structure, yes, but not immune. A traumatic injury should not be interpreted as just any overload, especially if the pain limits movement or there is deformity, swelling, or inability to bear weight.

Prevention is built away from the moment of pain

The best prevention does not depend on a single routine, but on a set of sustained habits. Structured training progression, glute and trunk strength, hip mobility, and sufficient rest are basic pillars for reducing the appearance of lateral discomfort. The hip benefits more from well-dosed strength than from heroic improvisation.

Running technique and load management also matter. Increasing mileage, intervals, or elevation suddenly usually takes a toll on the tissue that stabilizes the pelvis. In practice, the side of the hip suffers when the stride becomes too long, when fatigue disrupts posture, or when the body tries to keep pace with muscles that are already struggling. Fatigue does not just weigh you down; it disrupts mechanics.

Outside of sport, it is worth taking care of hydration, bowel regularity, and everyday ergonomics. Spending many hours sitting, always crossing the same leg, or repeating movements without balance can irritate the area. The small tensions of daily life, added together, end up feeling like one big ache. Pain rarely appears out of nowhere; it usually builds its home little by little.

A lateral ache that calls for clinical assessment, not shortcuts

Pain on the left side of the hip has an inconvenient virtue: it forces you to think. It can start in a tendon, in a bursa, in the back, in the intestine, or in the kidney, and each source points to different decisions. That is why location alone is never enough. What matters is the full pain pattern and its accompanying signs.

For runners, the temptation to label everything as overload is understandable, but it often oversimplifies too much. Some discomfort improves when load is reduced and strength is rebuilt; others require tests or urgent care. The difference between them is not marked by the internet, but by the combination of symptoms, examination, and context. Listening to that combination, without melodrama but without carelessness, is usually the best first step.

The left hip, after all, works like a crossroads. The stride, posture, breathing, and also signals from nearby organs all pass through there. When it hurts, the body is not just warning you: it is asking to be read in detail. And that detail, in health and in sport, often changes the outcome.

Medical reference: Hip pain in adults, NHS.