(Reuters Health) - After a water rescue, lifeguards need to actively help their muscles recover so they’ll be ready for the next call to perform, according to a small study from Spain.
Recovery exercises involving running or using foam rollers for an intense muscle massage both cleared out much more of the lactic acid that collects in the blood after a burst of exertion than just resting, researchers found.
Excess lactic acid in the bloodstream can limit muscle performance and hinder subsequent rescues, the study team writes in the American Journal of Emergency Medicine.
“Drowning continues to be one of the leading causes of death worldwide in the absence of disease,” said one of the authors, Roberto Barcala-Furelos of the Universidad de Vigo in Santiago de Compostela and the International Drowning Research Alliance in Rio de Janeiro, Brazil.
More than 360,000 people drown every year, according to the World Health Organization.
“However, the prevalence of drowning deaths on supervised beaches is very low relative to beaches that are not monitored,” Barcala-Furelos told Reuters Health by email. “Lifeguards are a key to avoid drowning, thanks to their prevention and rescues.”
To see what most helps lifeguards recover after a rescue, the researchers set up an experiment with 12 surf lifeguards on a beach near Marin, a coastal town in northwestern Spain. To recreate a typical rescue, each lifeguard ran 10 meters (about 11 yards) to the ocean, swam 100 meters with fins to an adult victim who was pretending to be unconscious, towed the victim 100 meters back to shore and pulled the victim onto dry sand.
All the lifeguards did this three times over three days, each time following the mock rescue with one of the recovery approaches.
The lifeguards’ average age was 24 and they all wore wetsuits during the mock rescues.
Immediately after each rescue, the lifeguards had their blood tested to measure lactate levels and reported on their perceived exhaustion. They then removed their wetsuits and began a 25-minute recovery period doing one of three activities.
The running recovery included 16 minutes of running at a moderate pace and five more minutes of walking. The foam rolling recovery included five exercises over 20 minutes that involved using body weight and foam rollers to deeply massage the muscles of each leg. The third recovery activity was simply sitting and resting for 20 minutes.
After every recovery exercise, the lifeguards’ blood was tested again.
Over a total of 36 water rescues by the 12 lifeguards, average blood lactate levels rose roughly three-fold immediately after the rescue. But after either the running or foam roller recovery exercises, the levels dropped by more than half. In contrast, just resting led to about a one-third decrease in lactate levels.
“Everyone engaged in activities requiring repeated and exhaustive physical effort could have interest in this,” said Damian Morgan of Federation University in Churchill, Australia, who studies drowning prevention but wasn’t involved in the current study.
One limitation of the study is its small sample size, the authors note. In the future, the research team plans to test how the recovery methods influence the day-to-day work of a lifeguard, what happens with lactate levels when a second rescue is performed and how other recovery methods can help rescue teams.
“The main question is . . . ‘Does it happen like this in the real world?’,” Morgan said by email. “Lifesavers often work in teams. They commonly use rescue boards or water craft. It’s unknown how often they are ever subject to the conditions specified in this study.”
“Of course, lifesavers in general benefit from recovering after a rescue,” Pertti Suominen of Helsinki University Hospital in Finland told Reuters Health by email. “In any location, we can help lifeguards by bathing in areas where we can be seen - and rescued promptly, if required. In drowning, every second counts.”