Hi Matthew,
Sorry to hear about the lower rankings. This situation totally sucks, I know.
Unfortunately, this situation is more and more common with infographics. By all rights, you should rank higher for this term. A couple reasons why this might be happening:
1. Over-optimized anchor Text: As the other commenter pointed out, most of your incoming links are the phrase "hot tub yoga". We see this in Open Site Explorer as well - http://www.opensiteexplorer.org/anchors?site=www.swimuniversity.com%2Fblog%2Fhot-tub-yoga-infographic
In the past year, especially since the Penguin updates, we've seen Google target this type of anchor text. When you get the same, repeating exact match anchor text for a phrase, it often triggers a filter which prevents you from ranking. Many SEOs now advise to use generic or branded anchor text as your link, such as www.example.com, which most likely won't be penalized.
Other SEOs advocate rotating your anchor text. Mike King recently wrote a post about this. http://blog.iacquire.com/2013/01/03/using-embed-code-randomize-your-links-anchor-text/
My personal preference goes a step further: don't use an embed code or specify an anchor text. Let folks know they can repost your infographic - even give them the file to do so - then simply ask for attribution. This way your anchor text is randomized, and likely carries more value.
2. The page may be over-optimized in other ways. I see this often when the title tag, URL, headline and anchor text all match up, Google sees this as over-optimization and will knock you down in rankings.
It's too late to change the URL (unless you want to do a rediret) But you can back off on the title.
3. Aside from the infographic, there's very little text on the page. And, of course, the words on the infographic are all an image. Adding a couple hundred words of unique text at the top, then adding an HTML text only version at the bottom could help this page to rank.
There's still a chance to turn this page around. New links (not optimized) may reverse a Penguin-like penalty, and you can add more content and alter the meta data of the page (not too much!)
Hope this helps. Best of luck!
It's possible that there's 100's or 1000's more we're not seeing, and these are causing either a manual or algorithmic penalty.