『Case of Low Back Pain Developed During Weight Training – An Approach to Lumbar Flexion Syndrome』

  • 2023.11.14
  • ∵ 整体

Case Study

A 26-year-old university student developed pain in the lower back and left lower limb while weight training. While carrying a 90 kg load and bending the knees in a prone position during the training, the student felt a bursting sound in the back and experienced severe pain simultaneously. Following this incident, specific exercises were halted, but other training continued.

The client, who works in a university laboratory, attends 2 to 3 classes per day. While sitting, severe pain is felt in the lower back and lower limbs. After self-diagnosing a hamstring injury, the student began doing forward-bending stretches. These stretches are painful but seem to reduce the pain afterward.

Two months after the injury, the patient was referred to our clinic. The patient continued intense training during this period, avoiding only the exercise that caused the accident. The patient had a history of left knee surgery following an injury and has since avoided running, focusing instead on weight training.


The client has been lying on the floor since the onset of pain. To alleviate the pain, pillows were placed under both thighs and knee joints, but changing posture only increases the pain. The pain during sitting is 7-8/10 in intensity, located in the lumbar region and the posterior aspect of the left thigh. The pain intensifies when getting up from a chair. Standing pain is relatively mild at 4-5/10. Reflexes of the Achilles and patellar tendons are normal, and there is no muscular weakness around the ankle and knee joints, with normal sensory testing.

Movement Analysis

• Forward Bending: Pain in the lower back and posterior thigh worsens during forward bending and lessens when returning to the upright position. Even supporting the trunk’s weight with hands and bending at the hips alone worsens the symptoms.
• Lateral Bending and Rotation: No specific problems are observed in these movements. Hip Flexibility: There is no shortening of the hip flexor muscles.
• Hip Abduction and External Rotation: No compensatory movements or worsening of pain are observed in these movements.
• Single-Leg Standing: Symptoms worsen when standing on the right leg with the left leg lifted. Lower Limb Extension Elevation: Lying on the back and lifting the extended left lower limb causes pain at 60° of hip flexion.
• Lying on the Side: No worsening of symptoms when lying on the side.
• Prone: Pain radiates to the lateral surface of the lower leg when lying prone, but placing a pillow under the abdomen alleviates the symptoms.
• Sitting: Symptoms intensify when flexing the lumbar spine in a seated position.

Muscle Length and Strength Analysis

• Rigidity of the Rectus Abdominis: The rectus abdominis is stiff, potentially contributing to the hyperextension of the lumbar spine.
• Muscle Strength: No significant muscle weakness is observed. However, the back muscles are not as prominently elevated as the rectus abdominis.

Consideration of Symptoms

• Spinal Flexion and Compression: It is observed that the client’s symptoms worsen with spinal flexion and compression. Contraction of the left hip flexor muscles (particularly the iliopsoas) also seems to intensify the symptoms.
• Symptom Relief: Symptoms are alleviated in standing and supine positions. Even if the leg extension test is positive, relaxing the hip extensor muscles reduces the symptoms.
• Forward Bending and Rotation Tests: Symptoms are exacerbated by forward bending, but no worsening is observed in rotation tests.
• Diagnosis: The observed symptoms may be diagnosed as lumbar flexion syndrome with radicular symptoms along the sciatic nerve.


• Exercises to Promote Lumbar Stability: Exercises to enhance lumbar stability during limb movements and daily activities were instructed, emphasizing avoiding excessive compression on the spine.
• Adjustment of Weight Training: Based on the client’s request, we continued the upper body strengthening program while advising against overhead weightlifting and exercises that could exacerbate symptoms.
• Correction of Misunderstandings and Advice: The client’s misunderstanding about hamstring stretching was corrected. Advice was also given to avoid prolonged sitting and excessive flexion of the lumbar spine.
• Supine Exercises: Exercises extending the hip and knee joints while using the abdominal muscles were instructed, stopping at the point where symptoms appear.
• Other Exercises: Instructions were given for hip abduction and external rotation, side-lying hip adduction and abduction, prone knee flexion and hip rotation (using a pillow), and quadruped lumbar extension and posterior rocking movements.
• Seated Exercises: The client was advised to avoid hip flexion and perform knee extension exercises.
• Standing Exercises: Considering the signs of neural tension, standing exercises were not recommended due to the potential for worsening symptoms.

Treatment Outcome

• Follow-up: The client visited every two weeks and underwent treatment for about four months.
• Treatment Effectiveness: During this period, he became able to perform posterior rocking movements from a quadruped position without symptoms. Additionally, symptoms in the prone position improved without the need for a pillow.
• Remaining Limitations: However, there are still limitations with sitting for more than 45 minutes and forward bending movements.
• Lower Limb Extension Elevation Test: This became negative, and complete extension of each knee joint was achieved. No symptoms of sciatica were observed.
• Muscle Strengthening Program: A back muscle strengthening program was initiated, starting with exercises that flex one shoulder joint while lying prone with a pillow under the abdomen. This movement was done to avoid numbness in the left leg. Similarly, shoulder flexion exercises were also performed in a quadruped position.
• Status After 6 Months: After six months, the client was able to sit for more than 45 minutes, and the weight training program was resumed using very light weights. The training in standing or sitting positions has been reduced from the previous 90 kg to currently less than 25 kg. However, support is still needed for forward bending movements.

Reference Books)