Adding exercise physiologists to ICUs can improve mobility and patient outcomes, according to the experience of three medical-surgical ICUs at Baylor St. Luke’s Medical Center in Houston.1

The addition of exercise physiologists was studied as part of a larger bundle of interventions intended to improve the quality of care for ICU patients. Each patient in the ICU during a three-month period was treated by an exercise physiologist at least once per day.

Exercise physiologists focus on improving strength, endurance, and mobility, but traditionally have worked in an outpatient setting, explains Claudia DiSabatino Smith, PhD, RN, NE-BC, co-author of the report and nursing instructor at Cizik School of Nursing at the University of Texas Health Science Center at Houston.

Most Patients Improved

Typically, without this kind of intervention, only about 8% of ICU patients are mobilized by physical therapists, says study co-author Yao Ababio, PhD-ChE, MBA, PMP, CSSBB.

“We knew that wasn’t enough. They had to depend on physical therapy and nurses, which was just a Herculean task,” she says. “It was more than they could handle, so we looked to exercise physiologists as a way to provide the more effective care for these patients.”

Almost all study participants (97%) maintained or increased mobility. Exercise physiologists are well known in the outpatient setting, particularly for cardiac and pulmonary rehab, notes co-author Petra Grami, DNP, RN, CCRN, NE-BC, CVRN.

“They are well established in those arenas and starting to trickle into inpatient care, partly out of the frustration with physical therapists — the missed visits, reduced number of visits, their limited training to deal with critically ill patients,” Grami observes.

“A lot of the core training for exercise physiologists is on the cardiovascular side,” Grami continues. “They know advanced cardiac life support, ECGs, pulmonary, and that cardiovascular training makes them the perfect discipline to migrate into the ICU setting. Physical therapists don’t have that focus on the pulmonary and cardiovascular side.”

Physical therapists also are limited on their billable skills, Grami notes. A patient with muscle atrophy after critical illness who is deconditioned or dealing with other “soft” mobility issues is a low priority for physical therapists, she explains.

The therapist may miss a scheduled visit with that patient in favor of someone who just suffered a stroke or is recovering from an amputation. On the other hand, exercise physiologists prioritize fragility, deconditioning, strength, and endurance, all issues that are significant problems for ICU patients.

Resistance From PT

Nonetheless, the project was not popular with physical therapists, who felt threatened by the hospital bringing in exercise physiologists to the ICU. “We met with them ahead of time to give them the opportunity to take an active role in our study and be involved in early, aggressive, progressive mobilization. They let us know that they really weren’t interested in mobilization because it wasn’t a billable skill for them,” Smith says. “That’s why we decided we needed to come up with a different way.”

Physicians had grown frustrated with the lack of mobilization in the ICU and were demanding a change, Grami says. Because so many study participants who received care from exercise physiologists improved or maintained their activity level, Smith says that was a strong endorsement of the concept.

“We know that maintaining is important because it is when patients are in the ICU that they lose so much of their mobility,” Smith says. “Simply maintaining their status quo was a gain.”

Baylor St. Luke’s hired three exercise physiologists to work 40 hours a week. The hospital sought master’s degree-ready professionals, but even at that level of education the exercise physiologists were cost effective when compared with physical therapists, Smith says. “The average salary is about 40% less than for physical therapists, so it’s a significant savings to hire an exercise physiologist instead of a physical therapist.”

Trained to Work in ICUs

The exercise physiologists underwent eight weeks of discipline-specific didactic education and structured, hands-on ICU training, Ababio says.

The evidence-based manual for training the exercise physiologists was developed by an interdisciplinary team, says co-author Cheryl Haseeb, BSN, RN, CCRN, who led the educational effort.

Their training emphasized safely working around the medical equipment common to ICUs, including the different lines and monitors on patients, Haseeb says. There were few safety issues related to the work of exercise physiologists, which Ababio attributes to the site-specific training they received.

“We emphasized the different things they may encounter in the ICU, such as orthostatic hypotension, how to recognize that when the patient sits on the edge of the bed and feels lightheaded, when to call for help with that,” Ababio says. “The training was comprehensive. That is different from what some organizations do with unlicensed practitioners like patient care techs and trying to train them for this kind of work. They’re running into lots of barriers, whereas we are starting with a highly trained person and just teaching them how to work in the ICU setting.”

The exercise physiologists worked under the direction of a registered nurse/delirium coordinator, an intensivist, and registered nurses. They coordinated their care with other members of the ICU team, including patient care assistants and physical therapists.

The hospital provided durable medical equipment specific to the exercise physiologists’ therapy needs, including a sit-to-stand mechanical lift device. They also could access bedside stationary bicycles, rolling walkers with seats, thoracic walkers, gait belts, and free weights.

Define Roles Clearly

Defining the roles of each participant was important in making the intervention work, Haseeb says.

“You’re changing the culture of the way things have always been and getting 100% buy-in from the interdisciplinary team is always going to be a challenge,” she notes. “That was a struggle initially, but we overcame it by clearly defining those roles.”

The Baylor St. Luke’s team knew they were making progress when physicians started calling the ICU to ask if an exercise physiologist could come to their units to conduct the same work with patients outside the ICU.

“They were frustrated because they saw what was happening in our units and they knew it would work with their population, too,” Smith adds.

To facilitate data collection with the project, the team at Baylor St. Luke’s worked with the exercise physiologists to create a data collection tool for various data points, including how long they spent with the patient and any barriers they encountered, but the team also provided a tool for nurses to collect data.

Smith and Ababio developed a measure to quantify the mobility progress of patients from the data collected by the exercise physiologists and the nurses. The Activity Mobilization Evaluation Scale is a 12-point scale that quantifies mobilization activity on a scale of 0 (indicating medical exclusion from activity) to 12 (indicating the patient walked more than 1,000 feet). The scale awards points for achieving mobilization goals such as exhibiting an active range of motion and standing at the bedside, as well as for measured ambulation distances.

“That proved to be a very powerful tool. It gave us the data to not just get the data transformed but to actually compare changes in activity levels,” Smith says. “Ours was the only study I found in the literature that could compare to that. The rest of them looked at outcomes to say how many patients got mobilized or if they got mobilized with a certain period of time, but we were looking more at quantification of the outcomes.”

It is important to dedicate exercise physiologists to a particular ICU so that they are familiar with that unit’s patient type and the care provided, Smith says.

The program has proven so successful that other departments within the hospital started budgeting money to hire exercise physiologists, Grami notes. “Now, most of the 13 ICUs have their own exercise physiologists, and even the neuro ICU is asking for an exercise physiologist. They want one even though you could argue that the ICU dealing with stroke patients is the appropriate area for physical therapists,” Grami says. “The ICUs have embraced this because they see how much difference it can make.”


  1. Smith CD, Grami P, Haseeb C, Ababio Y. Exercise physiologists: Key to providing early mobilization in the intensive care unit. Am J Crit Care 2019;28:385-392