The market for wearable fitness trackers that can record basic metrics such as steps taken and heart rate has expanded rapidly in recent years. However, the future of this space involves more than just wearing a band on your wrist. Here's how Google (NASDAQ:GOOG) (NASDAQ:GOOGL) and Under Armour (NYSE:UAA) are showing us the future of "connected clothing."

Google's "Project Jacquard"
At its Google I/O event in February, Google demonstrated some of the fascinating new ways it's trying to make digitized fabric. Its "Project Jacquard" builds electricity-conducting yarn into regular garments, essentially making touchscreens that are flexible enough to wear.

This technology isn't completely new. There are tech start-ups, such as Athos, that have been working in this space for some time. However, with Google's scale and technological resources, as well as a partnership with clothing company Levi's, this technology could be accessible at a consumer level very soon. As of now, there is no date set for when connected Levi's garments might be sold to the public, though. 

Under Armour shows us how applicable connected clothing could really be
While Google's technology is fascinating technically, it's Under Armour that's showing us how the idea could be applicable at a consumer level. Under Armour CEO Kevin Plank estimates that within the next five years, 50 billion retail items will have a connected chip.

"If we believe that our future is going to be defined by these hard pieces of glass or plastic that sit in our back pockets, you're crazy. It is going to convert into apparel," Plank said, as reported by the The Wall Street Journal.   

As an apparel company with an increasingly large tech focus, Under Armour plans to be on the forefront of connected apparel. There are the obvious athletic and fitness advantages, such as having sensors throughout your athletic gear to monitor specific movements and provide coaching at a more specific level than any human coach would be able to. This side of connected clothing plays well into Under Armour's push for connected fitness tracking, including a platform of fitness apps that together already have over 140 million users.

From Under Armour's 2013 "Future Girl" advertisement. Photo: Under Armour.

However, Under Armour's loftier goals include ideas such as personalized temperature control. Plank has made comments about how inefficient it is that we control the temperature in our entire house or office for just a few small bodies. Why not allow our digitized clothing to regulate temperature for us instead? This is just one of the many uses of connected clothing that could make this a disruptive technology in the coming years.

Investing takeaway
IDC has reported that the wearable-tech market exploded in 2014, growing faster than any other segment in the consumer-electronics market. IDC also projects this market to reach 155.4 million annual shipments by 2019, up from about 26.4 million last year.   

Basic tracking wearables have gained a lot of momentum recently, and rightfully so. These devices make fitness and biometric tracking very accessible on a mass level through their low cost and convenience. However, the applicability of having that same technology covering one's entire body will expand the market far beyond just those interested in tracking basic stats such as steps and heart rate.

It's still early, as neither Google nor Under Armour has come out with connected apparel products that are available to consumers on a mass level yet. But when they do, we can probably expect to see market growth far beyond the current wearable-tech market. So far, it looks like these are the two companies that will dominate this space. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.