“It could take seconds, or it could take years,” for weightlifting to cause a bulging disc, says Dr. Michael Perry, MD, member of the North American Spine Society and American College of Sports Medicine.

I was inspired to write this article after the fitness director of the health club, where I used to be a personal trainer, walked in one day with a slow, tentative gait. I asked him what was wrong and he said, “I blew out a disc leg pressing.”

Dr. Perry explains, “Typically, anyone who uses their back in any type of physical activity will have generalized wear and tear. With that, the disc and spine will become degenerative over time and that, in itself, can cause a bulging disc.”

In the fitness director’s case, it took seconds: a single, acute event.

Though the floor leg press machine is supposed to stabilize the back (and it does, relative to the instability of the back squat and deadlift), the lower spine can also be subjected to high levels of stress if you’re straining from a very low position to push up a very heavy sled.

If your butt is off the seat at this point, this makes those lumbar discs even more vulnerable.

This is why I recommend that if you’re going to press from a very low position (knees by armpits), to use no more than a moderate amount of weights, e.g., that which you can press for at least eight reps.

Dr. Perry continues, “Chronic condition: A former acute injury to the spine can accelerate the degenerative process. If you have an acute back injury, 10 years down the road you may develop additional pain.

“This isn’t related to new trauma, but related to the injury from 10 years ago. That injury accelerated the degenerative process.

“Acute condition: If you’re a weightlifter, any time you apply pressure to your spine (whether you’re doing deadlifts, squats, bench pressing, etc.), you can herniate [bulge] a disc or cause nerve compression.

“In rare cases, this disc herniation in the lower back can cause cauda equina syndrome – when the nerve roots at the end of the spinal cord are compressed [causing paralysis, numbness, incontinence]. Cauda equina syndrome develops rapidly and is a surgical emergency.”

Does this mean avoid squats, deadlifts and leg presses because lifting weights might cause a bulging disc? Of course not.

Lack of weight-bearing exercise is far more dangerous, because the individual who never strength trains and then one day is helping a friend rearrange some furniture, shoveling snow or just leaning forward to pick up a potted plant…can “throw his back out” and require immediate medical attention.

Or, an extra-long session of housework or yardwork could render a non-strength-trained person in bed all day the next day due to back pain.

When lifting weights, you must use picture-perfect form, and to build strong or big muscles, you do NOT have to gun for the one-rep max.

But even if you do eight reps, you must pay strict attention to textbook form.

I see so many people performing deadlifts and back squats with lousy form; they risk getting a bulging disc.

Dr. Perry is chief medical director and co-founder of USA Spine Care & Orthopedics, and is frequently sought out for his minimally invasive spine surgery expertise.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.