It is the justification that undoes diets and causes weight-loss plateaus: “It’s ok, I worked out today.”  Even worse, “It’s ok, I’ll work out tomorrow.” 

Most people overestimate the calories they burn during workouts and underestimate the calories they consume. Even as a longtime ballet dancer and avid devotee of Bikram yoga and Pilates, I too have been guilty of the occasional post-workout overindulgence. Online information, while helpful for a rough estimate of calories burned, is often incorrect or misleading. Take the estimates for a Bikram Yoga class calculated using my weight and the duration of exercise. Low estimates gauge a 90-minute session to burn 598 calories while the highest reach 748 calories.

Using online information may lead to underperformance and overindulgence, but fitness monitors that can respond to the intensity of exercise by measuring heart rate are becoming more accurate and sophisticated. The Digifit iCardio app allows users to track their fitness progression.

Digifit, touting itself as “the original heart-rate monitoring app for smartphones,” recently launched an Android-compatible iCardio App.  The app only costs $1.99, but users cannot monitor their heart rates in real-time without a pricey heart rate monitor ($79.95-$99.95). Also, while Digifit’s most common heart rate monitor, a chest strap, lends itself well to running and biking, it is not suitable for all types of exercise. Anyone who has taken a Bikram yoga class in a 105 degree studio can sympathize with my horror at the idea of wearing an additional tight strap around my chest.

Similar fitness monitors also have limitations when it comes to improving form. In exercise programs that focus on presentation and postures—like yoga and ballet—improving form is akin to water cutting through rock. Fine-tuning positions and presentation is a gradual process performed over years of training with an experienced teacher. Each time you practice, you are supposed to push to your edge of flexibility and strength. Alone, a fitness monitor cannot tell you if you are straining your hip or overextending your arms. In short, you may burn a lot of calories while injuring yourself.  

Two concept technology products from Electricfoxy seem to solve the problems posed by current fitness monitors. The first, a fashionable ring called Pulse, would measure the wearer’s heart rate and sync with a mobile app in order to track calories burned. The ring would also chart if the wearer was in an optimal training level and glow different colors when activated: white for optimal activity, blue for below, and red for above.  

A prototype of Electricfoxy's garment Move.  While ditching the bulky arm or chest band may not seem like an option, recent work with improved polymer materials and lower-cost thin-film processes would make Pulse more viable. Rather than mounting electronics onto flexible plastic substrates, some companies, like MC10, are embedding silicon die into plastic substrates. This process only opens the door wider for flexible electronics, and MC10 is currently developing a wearable fitness monitoring device with Reebok using the embedded silicon die technique.

Electricfoxy’s second prototype, Move, is a smart garment that would connect to a mobile app and alert the wearer, through haptic feedback components, whether her movements were incorrect. The applicability of Move for yoga, Pilates and dance is particularly exciting. Rather than needing an instructor (and hundreds of hours of practice) to perfect form, wearers would be able to improve with Move’s automatic feedback.

The improved muscle memory that Move creates would also be useful in areas other than trendy yoga studios. Consider how such a garment could help athletes avoid injury and enhance performance. During a typical season, half of all starting MLB pitchers go on the DL. Rather than blaming overuse and poor mechanics, clubs could use Move to limit injuries. In terms of medical use, Move could help the muscle memory of patients undergoing physical therapy. The economy of movement that Move facilitates would help people recover from injuries using the least amount of effort.

Mass production of Move and Pulse seems far off, but increased pioneering of silicon die and e-textiles makes the two products seem less unrealistic. Even without moving from conceptual to operational, Electricfoxy’s designs demonstrate the potential for fitness monitors beyond calorie counters. Instead of merely providing a justification for indulging, fitness monitors have the potential to maximize results while minimizing strain and injury.