Ballistic strength training is usually the domain of elite athletes.

But, in a world-first trial, Australian physiotherapy researchers will put the power development training to the test in a bid to improve the mobility of patients with traumatic brain injury.

The four-year project, which has received National Health and Medical Research Council (NHMRC) funding, will study the impact of ballistic strength training on more than 130 patients at sites in Sydney and Melbourne, including Epworth HealthCare’s acquired brain injury rehabilitation unit at Richmond, the largest brain trauma rehabilitation centre in Australia.

Dr Gavin Williams, a neurological physiotherapist at Epworth HealthCare and a University of Melbourne researcher, says research shows traditional strength training, in related fields such as stroke and cerebral palsy, is not effective for progressing patients’ walking.

“We did a big review of all of the trials ever done to use strength training to improve people’s walking, and that was 27 trials that have been done around the world,” he says.

“We knew that it wasn’t working particularly well so instead of just reinventing the wheel, I wrote to all the authors around the world and asked them to send me their protocols.

“What we found was people were primarily focusing on the muscles that act on the knees, so your quads, your thigh muscles and your hamstrings, and they are the biggest muscles in your legs and they’re also the biggest muscles in your body, so they’re obviously important.

“But in terms of actual walking, they don’t contribute that much - so despite making the quads and hammies a lot stronger, the patients weren’t actually walking any better.”

Dr Williams says strength training exercises have traditionally been performed very slowly, where the patient takes one or two seconds to complete an exercise, such as a leg press.

“Instead of making someone simply stronger we’re trying to make them more powerful. The difference between strength and power is the speed at which you move,” he says.

“During walking, the movements happen very quickly and people don’t appreciate it because you just think of it as normal everyday walking but the speed at which the muscles act is very, very quick.

“For example, when you walk, the time that your foot is actually on the ground is about 0.6 of a second and the time that you actually use your calf muscle, which is the most important muscle for walking, is only 150 milliseconds.

“It’s extremely quick so it’s no wonder that slow exercises don’t then translate into fast movements during walking.”

Dr Williams and his team have piloted, tested and refined an exercise program where patients perform fast or ballistic strength training with a biomechanical approach - focusing on the function of how the muscles contract during walking.

“We’ve had to do a lot of preliminary studies and testing to firstly identify that it is actually muscle weakness that’s the main problem and not other things like balance or spasticity and look at how strength changes as patients recover and look at how power changes as those people recover.

“Through a series of about a dozen strategies we’ve been able to demonstrate and focus on power generation as the key problem and then come up with a training strategy to address the problem with poor power generation.

“It’s a model that’s normally delivered to sportspeople and we’ve just modified it to the patient level and done that testing - no-one’s actually done this type of strength training before in neurological rehab.”

The trial will test the impact of the program on not just walking but also on high level mobility, such as running, hopping, skipping and jumping.

Traumatic brain injury is the main cause of disability for the young adult population. Most traumatic brain injury patients are road trauma victims, often males aged 18 to 25.

Dr Williams says while traumatic brain injury patients sustain horrific injuries, often including multiple fractures, it’s the recovery of their brain that determines their progress through rehabilitation.

He hopes the trial will demonstrate the power of ballistic strength training for neurological patients and change the way physiotherapists deliver treatment to patients with traumatic brain injury.

“I like the field because it’s young and reasonably dynamic and despite these terrible injuries if they survive the accident then their rehab takes quite a while - it’s not unusual for someone to be in the process of rehab for a year or two,” he says.

“They have five or six or seven decades ahead of them so we need to make sure that we obtain best possible outcomes for these people and reduce that residual disability so that they are active and functioning as best they can.”