Black History

Kevin Woolfolk: The Innovator Behind the Modern Hamster Exercise Wheel

Recognizing the potential value of his invention for other pet owners and researchers, he patented his improved hamster exercise wheel, making him the known inventor of this type of measuring device. His patent (US 5,649,503) describes “a squirrel cage” with “a cyclometer having a sensor mounted on the support and a trigger mounted on the cylinder such that when the cylinder rotates, the trigger passes near the sensor.”

Published

8 months ago

August 25, 2025

Tamara Shloh

Design sketch courtesy of Kevin Woolfolk.

By Tamara Shiloh

In the world of pet care innovation, some of the most impactful inventions come from the simplest observations. Such is the case with Kevin Woolfolk, an inventor whose curiosity about his pet hamster led to a revolutionary improvement in small animal exercise equipment that continues to benefit pets and their owners today.

There isn’t much written about Woolfolk’s life, but his story begins in 1969 when he was exercising on his stationary bike one evening in Normal, Illinois. As he diligently recorded the mileage of his workout, he noticed his hamster, Burt, running energetically on his wheel. This simple observation sparked a question that would lead to a significant innovation: just how far was Burt traveling during his nightly runs?

Unlike many inventors who start with complex technical problems, his inspiration came from genuine curiosity about his pet’s activity levels. He wondered about the distance Burt was covering as he ran on the traditional hamster wheel, which at the time provided exercise but no way to measure the animal’s activity.

Driven by this curiosity, Woolfolk created a prototype that could measure his hamster’s exercise routine. His solution was simple: he constructed a mouse wheel equipped with a small magnetic counter purchased from a local store. This addition transformed the basic exercise wheel into a device capable of tracking the distance traveled by the animal.

After placing the prototype in Burt’s cage, Woolfolk left his hamster to complete his nightly exercise routine. The results were astounding — upon waking up, he discovered that Burt had run an impressive 23,300 feet, equivalent to roughly 4.5 miles. This revelation not only satisfied his curiosity but also demonstrated the significant exercise needs of small pets like hamsters.

Motivated by this eye-opening figure, he decided to put his creative juices to work. About a year after drafting the idea, he filed and was granted a patent for a “squirrel cage having a cyclometer … and method for monitoring the activity of an animal.” The patent detailed the mechanics of effectively tracking the animal’s activity via wheel rotation.

This innovation represented more than just a gadget for curious pet owners. The ability to measure small animal exercise provided valuable data for veterinarians, researchers, and pet enthusiasts who wanted to better understand and monitor their pets’ health and activity levels.

Woolfolk’s invention has had lasting impact on the pet industry. His idea was eventually picked up by pet companies and commercialized, making the measuring hamster wheel available to consumers worldwide. Today, variations of his design can be found in pet stores and are used by hamster owners who want to track their pets’ exercise routines.

Tamara Shloh

Posts by Tamara Shloh

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Activism

Oakland Post: Week of April 22 – 28, 2026

The printed Weekly Edition of the Oakland Post: Week of April 22 – 28, 2026

Published

7 days ago

April 25, 2026

Oakland Post

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Oakland Post

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Mayor Barbara Lee Proclaims April 9 as ‘100 Black Men of the Bay Area Day’

“Today, the 100th day of the year, I proclaim 100 Black Men Day,” said Mayor Barbara Lee standing with newly appointed Oakland Port Commissioner Derek Mohammad, a 100 Black Men member. “Whereas the 100 Black Men of the Bay Area has demonstrated decades of unwavering commitment to uplifting youth and strengthening families and advancing opportunity and access in Oakland and the greater Bay Area with their signature programs…the chapter has impacted thousands of young people and contributed thousands of hours of community service…”

Published

2 weeks ago

April 19, 2026

Oakland Post

At D. Monaghan’s on the Hill, a resolution declaring April 9 ‘100 Black Men of the Bay Area Day’ was witnessed by (l.-r.) 100 Black Men leaders Maurice Harold, Marco T. Lindsey, Danny Lee Williams, Oakland Mayor Barbara Lee, Oakland City Council President Kevin Jenkins, Port of Oakland Commissioner Derek Mohammad, and Oakland Councilmember Janani Ramachandran. Photo by Carla Thomas.

By Carla Thomas

When Oakland Mayor Barbara Lee announced that she would proclaim Thursday, April 9, as “100 Black Men of the Bay Area Day,” the organization’s board chairman and owner of D. Monaghan’s on the Hill, Danny Lee Williams knew he wanted to mark the historic moment with fanfare his community could share.

Standing at the podium on the patio of his restaurant in the Oakland Hills, he welcomed about 150 members of the organization and the broader community who gathered to celebrate.

“This is a special day, and we are in the midst of our Economic Empowerment week,” he said. Williams also welcomed four vendors to sell their gifts and accessories during the event free of charge.

Lee shared how as a single parent of two boys, she was grateful to have the organization’s support in mentoring her sons.

“Today, my adult son is a member in Illinois, and I thank the organization for supporting so many Black boys.”

The idea for the proclamation originated with Oakland City Councilmember Kevin Jenkins, who praised the organization for its leadership and contributions to Oakland and the greater Bay Area.

“This work that we do would not be possible without partnerships with organizations like the 100 Black Men,” said Jenkins. “We’re saving lives, restoring communities, and giving people hope and opportunities.”

“This is Oakland,” said Mayor Lee. “This is what we’re about. It’s about new ideas, thinking outside the box and being who we are. It’s about bringing joy. This is our holiday.”

The mayor also thanked the organization for volunteering during Oakland Cleanup days.

Councilmember Janani Ramachandran added that while many complain about problems in the city, “the 100” put in the work.

“It’s hard to be in the community and do the work, but that is exactly what the 100 Black Men does,” she said.

The organization’s economic chair and associate director of Diversity Equity and Inclusion at the University of California Berkeley’s Business School, Marco T. Lindsey, shared his enthusiasm for change.

“Today is the culmination of our work and something special is happening in our organization and our city,” he said. “We have a special opportunity to show up for our community now in ways that we haven’t had in the past. We have a mayor that supports us and it’s important that each and every one of us do our part. We all need our fingerprints on whatever we want to see in our city.”

Lindsey also expressed that if underserved youth and their parents had access to the resources needed for success, “Our youth wouldn’t be breaking windows and joining gangs if they had a pathway to earn $75k to $100k a year.”

The 100 Black Men were hosts of an Economic Empowerment Forum at McClymonds High School on April 11 educating students on entrepreneurship and financial literacy. On Sat., April 18, they will hold their fifth annual Career Expo at Contra Costa College 2600 Mission Bell Drive (G225) in San Pablo from 8 a.m. to 3 p.m. The 100 Black Men chapter of the Bay Area was established in 1988, one of the earliest in the nation.

For more information visit 100blackmenba.org