March 21, 2017
Albert Mendoza is grateful for the opportunities he’s received at UMass Amherst. Mendoza, a doctoral candidate in Kinesiology, was recently awarded a Summer Dissertation Research Fellowship from the Graduate School. The $4,000 award will help him pay living expenses over the summer months while he completes his dissertation. His study, titled “A Comprehensive Validation of Activity Trackers for Estimating Physical Activity and Sedentary Behavior in Free-Living Settings”, examines the accuracy and precision of over a dozen physical activity monitors, some only available to researchers and some, like FitBits and Apple Watches, which the public is using.
The Graduate School awards the fellowships to support doctoral and MFA candidates from diverse backgrounds while they complete their dissertations or MFA theses. The goal in providing the fellowships is promoting diversity on campus, and in academia in general.
“Students from a wide range of backgrounds and experiences bring fresh perspectives and insights to their departments, disciplines, and the UMass campus,” notes the school on its website.
Emeritus Professor Patty Freedson, who mentored Mendoza at UMass, nominated him for the award. Still, he wasn’t sure he would receive it.
“I wrote a personal statement, and it was literally like summarizing my whole life in three pages,” he notes. “I felt like I had to be honest about my background, what is unique about me, and even my past mistakes.”
“After all that, when I first found out I was getting this fellowship, I thought ‘Are they sure they have the right person?’” Mendoza says.
The fellowship will help him complete a study that will break new ground in the use of physical activity monitors.
“A lot of studies have examined accuracy of activity trackers in lab settings, but this will be the first published study that tests their accuracy and precision in free-living settings using direct observation methods developed in our lab as the reference tool to measure energy expenditure, activity minutes and steps,” Mendoza explains. In fact, some of the devices have never been validated in a free-living setting at all, such as the Hexoskin-a biometric shirt with multiple sensors built into the garment’s fabric.
What the study is tracking are the activities of 32 participants as they go about their daily routine, comparing data from the monitors with his team’s direct observation methods about the energy a subject’s body is using. Mendoza and a team of undergraduate assistants he calls his ‘Dream Team’ create the comparison calculations by coding video of the subjects and rating the energy used for each activity, sedentary behavior, and manually counting steps.
“The lab studies are a great first step, but that’s not how these monitors are used in real life. That’s what we’re trying to get at,” he adds.
In order to track a wide range of daily life, each subject participated in three sessions of two hours duration. Each participant was tracked during one morning, afternoon, and evening timeframe. During this time, researchers tracked participants with cameras and monitors as they did everything from chores like dishwashing, to 12-mile runs, and even a jam session of music at a local Irish pub.
“You can’t just like this sort of work,” says Mendoza, explaining he was at every activity monitoring session, which alone totaled 192 hours. “You have to love it,” he adds.
Although many of the participants’ days encompassed the same activities, Mendoza notes they often expended different amounts of energy and accumulated different step counts. For example, several participants taught classes while they were being tracked, but with very different styles.
"We don’t have the exact numbers yet, but one subject taught an engineering class and wrote math equations across four blackboards, erased the board and wrote more equations a total of three times. The other professor pretty much stood in one place while teaching a large lecture of approximately 400 students,” he explains.
While Mendoza is thankful for the support of the Graduate School, he notes that it is one of many boosts he has been lucky to receive in his journey. One thing he plans to do when he finishes his dissertation is cook a meal and invite all the folks who have helped him along the way: faculty mentors, undergraduates on his ‘Dream Team’, his dissertation committee, his extracurricular runner’s group-The Shutesbury Coffee Cake Club, and even the study participants.
“Growing up, a big part of how we show we love you in our culture is with food,” explains Mendoza, who is Mexican-American. “I look at it as a personal gift from me to say thank you.”