One minute, you feel invincible: You’re squatting heavy, tossing bags of mulch, helping the lovely passenger in 12D hoist her bag into the overhead compartment. The next, your back barks, leaving you hunched over. Researchers at the University of Sydney recently studied 1,000 patients to pinpoint some of the most common triggers of acute back pain—those sudden, sharp spasms that seemingly occur at any time and can leave you laid up for days. Read the full article for Men’s Health.