In this video from Industry Focus: Consumer Goods, Motley Fool analysts Vincent Shen and Sarah Priestley break down the major tailwinds that have helped activewear become one of the most important parts of the apparel industry. But within this trend, it is the women's segment that has shown the greatest potential for growth.

A full transcript follows the video.

This podcast was recorded on Jan. 17, 2016.

Sarah Priestley: The good news is, last week, we ended on a bit of a down note about gym attendance, but actually, the average gym member visited their gym over 100 times last year, which is an all-time high. It's looking like that trend is set to continue for this year. Gym membership has grown 18.6% between 2008 and 2014, and the trend continued into 2015, which is when our last full set of data is for. The other good news, the other good aspect of this, is that it's not just gyms. We focus on gyms and we talk about gyms a lot, but there's a variety of ways for people to get involved in fitness activities, and there's more ways than ever before. If you actually look at runners in the U.S., women made up 57% of runners in competitive races. Globally, actually, female race participation is up 25%, compared to men at 7%. So, obviously, we're seeing that overall, there's an increase in participation, but it's actually swayed much more toward women.

Vincent Shen: That gives it away for our main coverage area for today. It's not just the apparel industry, but within that ... there are a lot of different ways to describe this, athleisurewear, activewear, sports apparel. Within that segment, the importance that women have played in terms of growth for a lot of these companies, and a lot of companies that previously were not involved in activewear launching lines, branching out. We will get to that. But, going further in terms of some of those numbers you mentioned about female participation in sports and things like that, I thought that a good proxy for this might be with high school sports participation in this country.

Priestley: Absolutely, yeah.

Shen: I think I pulled some of these numbers last year during a show that I did with Sean. The idea was, high school sports participation overall is up again for the 27th consecutive year. That's according to the National Federation of State High School Associations. They do an athletics participation survey, and they actually have data going all the way back to 1971. Some very telling, interesting numbers here. The surprising thing to see is, back in 1971, the first year of this survey, there were approximately four million total participants in high school athletics that year, and about 93% were boys, with the remainder obviously being girls. Thirty years later, by 2001, total sports participation was up over 70% from that four million number. But now, the mix is starting to shift. Girls, instead of just making up 7%, they made up 90% of that growth that we saw from 1970. Now, jump forward another 15 years, in 2016, total participation up over another 16% from that 2001 level. Girls growth outpaced that. Since the early 1970s, girls' participation has grown from 7% to over 42%. I think that really speaks to what we're going to talk about today, these longer-term trends shifting in favor of sports over years and decades. Can you give us an idea of what the activewear market overall now looks like?

Priestley: Yeah. It can be difficult to measure, because as we were talking about before the show, it depends what people are taking into consideration when they measure activewear. Overall, just to give you context, the U.S. retail apparel industry is about $225 billion, so per capita spending is about $1,000 per person on clothing and everything else. Activewear, as a portion of that segment, is estimated anywhere between $44 billion to $80 billion. I will caveat all of that by saying it depends on what they're taking into consideration. But, really, what we're trying to demonstrate is that it's actually growing to be a huge portion of the overall retail clothing market in the U.S.

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