Wearable fitness products are all the rage these days, but most of the ones on the market only track heart rate and location, and sometimes temperature and orientation. Students from Northeastern University in Boston have developed Squid, a sensor-laden compression shirt, smartphone app, and Internet portal that measures and records muscle activity. The shirt contains four EMG sensors (the "tentacles") that track muscle activity, essentially recording the number of repetitions of a resistance exercise. It also monitors heart rate activity so you can get a complete overview of your weight lifting sessions. All the data syncs with a companion smartphone app that in turn syncs to Squid's Internet portal. It'll keep track of your workout history, but you'll probably want to keep your workout partner to motivate you to do that one last rep.

Here's a video about the Squid:

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