Wired Writer Tests EMS Suit to See If It Can Replace an Hour of Exercise

EMS has been commercialized since the early 19th century and is now widely used in rehabilitation and to boost strength and stamina, the report explains. The principle is that electrical pulses create thousands of muscle contractions in a short time, far more than standard reps. Users still have to flex and activate their muscles; they cannot simply lie down and get in shape.

Studios such as Body20 and Manduu already offer guided EMS sessions, promising full-body workouts in 20 minutes or less. Pepper's home-use suit costs $1,400, the cheapest the reporter found, while competitors include Apeborn's $4,000 suit. At least five companies currently sell such suits.

The report cites several studies on EMS. A 2021 meta-study found significant effects of whole-body EMS on muscle mass and strength parameters, but not on body fat mass. A 2012 study on trained athletes measured benefits after three to six weeks: vertical jump height increased by up to 25 percent and sprint times improved by up to 4.8 percent. A 2023 meta-analysis concluded that eight weeks of continuous resistance training combined with daily upper body, lower body, and abdominal EMS training significantly improved muscle mass and upper body strength, and reduced body fat percentage in healthy subjects.

Physicians interviewed by Wired offered varied opinions. Andrew Mock, a primary care physician in Newport Beach and five-time winner of California's Strongest Man competition in the lightweight division, said EMS had proven beneficial for rehab or critical care patients with severe mobility restrictions, but healthy patients were unlikely to see much value. "If you go outside and start shivering, those are muscle contractions," he said. "But shivering doesn't make you stronger."

Ethan Kellum, team doctor for the NFL's Tennessee Titans, said he uses a form of EMS not just for rehab but also to supplement his own workouts. "It's really a function of the nervous system," he said, noting that in older patients muscles can become unresponsive and "go to sleep." When used appropriately, he said, EMS can improve the efficiency of communication between the nervous system and the body. "Add it to what you're doing. It can be really helpful."

Joseph R. Hribick, a professor of physical therapy at Lebanon Valley College, offered a middle view. "Current research does not suggest that EMS alone is superior to strength training for developing strength," he said. "Instead, it should be looked at as a tool to complement strength training and not replace it."

The reporter, after speaking at length with Pepper founder Emilia von Keyserlingk, agreed to test the suit. The garment resembles a spring-weather wetsuit that stops at the knees and elbows, and putting it on takes some effort. The reporter worked out with the suit three times a week for two months, while maintaining regular cardio and strength-training workouts and keeping diet and daily routines the same, to mimic the 2023 study.