(1) Muscle spasms
Muscle spasms or cramps are quite common. They can happen at any time of the day, but especially during exercise or in the days following a workout. They are commonly caused by muscle overuse, nerve compression, lack of blood flow, dehydration.
Muscle spasms in the lower back often occur when you are bent over and lifting something, but they can happen during any movement involving your lower body.
(2) Strained muscle
A strained or pulled muscle occurs when a muscle is overstretched or torn. It’s commonly caused by overuse, physical activity, lack of flexibility.
(3) Herniated disc
The spine is made up of many parts including spinal discs and vertebrae. If a disc slips, it means that the soft center of the disc has bulged out, which can irritate the nearby spinal nerves. A slipped disc may be accompanied by severe shooting pain.
Spondylolisthesis is caused by an injured vertebra shifting or slipping forward on the vertebra directly below it. More likely in younger people who participate in sports like gymnastics and weightlifting, spondylolisthesis is often the result of untreated spondylolysis. Spondylolysis is a stress fracture or crack in the small, thin portion of the vertebra that connects the upper and lower facet joints.
Lower back pain may be the result of arthritis. Your joints are protected by cartilage, and when your cartilage deteriorates, it can cause pain and stiffness. There are many different types of arthritis, including osteoarthritis, psoriatic arthritis, rheumatoid arthritis.
The back pain you are feeling when you bend over is likely due to a muscle pull or strain. It could, however, be something more serious such as a herniated disc. If you are experiencing severe back pain, blood in urine, changes in bowel or bladder habits, pain when you lie down, or fever, you should get medical help right away.
If your back pain does not go away or improve over time, schedule an appointment with your doctor for a full diagnosis. https://www.nhs.uk/conditions/back-pain/