Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Nautilus (NLS), a consumer fitness products maker, shed as much as 10% after receiving an analyst downgrade before the opening bell.

So what: Research firm B. Riley & Co. dropped its rating on Nautilus to neutral, from buy, and set a price target of $10 on shares. The price target represents just 2.4% upside from yesterday's closing value, and was based purely on valuation.

Now what: Regardless of how we feel about any particular stock, we have to remember to take analyst actions with a grain of salt as they're often short-term movers of stock prices, and rarely affect our long-term investing thesis. In this case, though, I do agree with B. Riley's analysis, as I noted in March with my CAPScall of underperform on Nautilus. My primary gripe -- in addition to being skeptical about consumer loyalty when it comes to fitness products -- is that Nautilus is overly exposed to an economic slowdown by relying solely on consumers to purchase its products instead of contracting directly with gyms. Even after today's drop, I'd suggest there could be further room for Nautilus to fall.