More people are strength training and injuries are spiking

Karen Towes, 52, has been fighting a nagging shoulder injury since September 2022.

The culprit was poor shoulder mechanics caused by long hours working at a desk and coupled with high-intensity interval training, lifting heavy weights through exercises such as deadlifts, squats and overhead presses.

“It has been long and tough,” says Towes of the recovery that involves treatment from a sports physiotherapist, regular massages to increase shoulder mobility and three cortisone injections to temporarily reduce pain and inflammation.

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She is still training with modified exercises at BFT, a global franchise that focuses on strength training.

“As a middle-aged female, this is even more important now. Incorporating weightlifting into my fitness helps me maintain my weight, muscle mass, bone density and generally a strong, fit and healthy body and mind.

“Interestingly, if I don’t exercise and keep up the mobility and strength training, the injury is worse.”

Strength training has jumped in popularity, especially among women, since the end of major Covid restrictions in 2022. That year, ClassPass, a subscription-based fitness app that operates in New Zealand, saw a 94 percent increase in customers choosing strength training classes. F45, a power-focused fitness programme, experienced record-breaking growth last year.

However, like other fitness trends, strength training comes with its own set of injuries. ACC data - and numerous interviews with physiotherapists and osteopaths - show that Towes is not alone in her shoulder injury. It’s the second most common gym or weight-lifting injury behind lower back injuries. In 2015, ACC reported about 24,000 shoulder and lower back injuries in either a gym, fitness training or from weightlifting in males and females. That number grew to almost 33,000 in 2024.

The data shouldn’t discourage people from lifting weights, but it should encourage them to exercise well, says Dr Margie Olds, a leading New Zealand shoulder physiotherapist.

“Do we want women lifting weights? Yes. Yes, we do. We want them doing that in a really sensible, progressive way so that they can both enjoy exercise and then maintain their bone health as they age.”

As a young physio, Professor Duncan Reid from Auckland University of Technology remembers the running craze of the 1970s and the corresponding injury set. There were problems with Achilles tendons and knees as well as stress injuries.

Similar injuries were brought on by the aerobics craze of the 1980s and 1990s when celebrities like Olivia Newton-John released aerobic videos. News reports in the 2000s blamed yoga for aggravating carpal tunnel in the wrists.

Futsal - or indoor soccer - was New Zealand’s fastest growing sport in the years before Covid with an injury set that plagued the lower limbs, including knees and ankles, Reid says.

Now, it's strength training with shoulders and lower back injuries.

“When we look at the literature around people that have looked at the epidemiology of weight training - CrossFit, power lifting, bodybuilding type events - then the main injury areas appear to be the shoulder [and] the lower back.”

For middle-aged women getting into weights for the first time, the injury risk might be greater, according to Jacinta Horan, a sports physiotherapist in Tauranga who is treating Towes. Whereas males in those middle age groups possibly could have lifted weights since they were teenagers, giving their body some preparation.

“People born in the 60s, 70s, 80s, and realistically in the 90s, as a general rule, exercise for most females was cardio, and that is starting to change, which is wonderful.

“But that population is still, I would suggest, relatively new in this space.”

However, the wear and tear of strength training is not a given. There are steps you can take to reduce your risk of injury, and patience is key, say Reid and Horan.

Take the time before each session to warm up, even if that means getting to the gym early and adding your own warmup to whatever warmup is offered in the strength class.

“Dynamic activity” such as cycling, rowing or running on a treadmill will get your body warmer, says Reid. Stretching will increase your range of motion. Doing the motion you are about to do slowly and without weights will prepare your body. For example, perform some squats sans weights.

“By getting yourself into that state, you’re going to reduce the chance of an injury.”

Towes blames long hours sitting sedentary at a desk for poor posture and shoulder mechanics - how bones, muscles, and joints move together. It eventually clashed with her strength training and resulted in her shoulder injury.

Osteopaths New Zealand chair Anj Young, who has a practice in West Auckland, views posture as a common start for shoulder injuries in strength training, especially for the high numbers of people who are picking up weights for the first time.

“For example, they want to do an eight-week challenge at F45 or whatever and maybe, they will get away with it until such time as the body's like, ‘I've had enough'.

“When you look at your shoulder positions or the way that you’re standing with your lower back, etc, this is potentially inhibiting your ability to get yourself into those movements, and that’s where it’s placing strain on those particular areas that I see coming through clinics.”

Horan suggests booking an appointment with a sports physiotherapist before jumping into a new form of exercise to assess basic strength, control and mobility.

“When they just go straight into it and unfortunately, potentially end up with an injury sooner rather than later, and then that limits their ability to carry on doing that form of exercise...”

Shoulder and lower back injuries are occurring in men as well as women during strength training. Tim Adams, a 22-year-old physiotherapist in Dunedin, has had both types of injuries from powerlifting, competitive weight lifting for squatting, bench presses and deadlifts.

The back injury happened when he was studying for exams, not sleeping well and eating poorly, "and then trying to train to my usual level, and not adjusting based on how I was feeling”, he says.

Adams’s shoulder injury happened soon after he got into powerlifting as a 17-year-old, and it was too much, too soon.

“I remember I was trying to get into a new sport, get into powerlifting at the time, and I wasn't under a coach or anything, so I was just pushing quite hard each session.”

The key is avoiding getting caught in the hype of a group fitness class or the honeymoon of a new exercise ritual, and slowly increasing the weight you are lifting, says Olds, the shoulder physiotherapist.

For a challenge at the age of 52, she is working on doing unassisted chin-ups. That looks like putting her foot in a thick exercise band to assist her with pulling her chin over the bar until she can’t do it anymore, which is about three or four repetitions. Over a few weeks, she progressed to a medium band and now only needs a thin band to assist her. The next phase: her goal of an unassisted chin-up.

“It feels great when, when you've exerted yourself, you get those endorphins and you get that buzz.”