Last year before we left for the World Rowing Championships in Linz, Austria, a teammate and I invested in some compression socks for the seven-hour flight to Germany. We had heard about the benefits of compression gear in athletic performance, especially while flying. Since we were racing just five days after arriving in Austria, we wanted to have as little recovery time as possible once we arrived. Did they help? I don’t have a lot of experience flying to Europe to race internationally to compare it to so it’s hard to tell. My feet didn’t blow up on the flight, but I’m also not prone to that sort of thing. I like to think that they did something, and I know that I’m not alone in investing in socks (or tights) for long flights to athletic competitions.
When I got home that summer, I took a bit of a break from rowing before I started training full time post-college in the fall. I did some hard runs and often wore the compression socks afterwards to help with recovery. I will say that my legs often felt better the day after wearing the socks, and I don’t think it was just mental. As I moved from Boston to Philadelphia to Long Beach, CA and back East again this past year (I still haven’t been in the same place for longer than two weeks since mid-April!), I forgot about the socks until I was finally starting to organize and unpack boxes the other week. I pulled them out and threw them in my suitcase for my next two-week adventure down to my cousins’ house in New Jersey, where I would start my half-marathon training plan.
I am wearing them today for the first time in about a year, post 5×2 miles at sub-half marathon pace in the New Jersey heat (note to self, work out before 8am next time). I am feeling pretty wrecked, so hopefully they can work some magic! I knew that they helped increase blood flow, but I decided to do some research to see more scientifically what the benefits are–other than making you look really cool, I mean ;). Should I actually run in them or are they better for recovery? Or should I not even bother?
Some people argue that compression gear can actually help performance when worn during exercise by clearing lactic acid more effectively, increasing VO2max, and raising the aerobic threshold. There have been several studies that have given evidence to these theories. These studies have only found slight increases in all of these factors, so depending on the type of athlete you are, these effects may or may not be worth it. For people looking to get a qualifying time for a race, every second counts, but for recreational athletes, don’t expect to see drastic performance increases! And, unfortunately for those looking to get a performance boost, many other studies have shown that there is no difference at all. 
Recovery is for what most people use compression gear. It is thought to improve blood flow; however the claims that it increases post-exercise lactate clearance have not been backed up by any studies. So while there is no physiological evidence, many athletes (like me) have found that their muscle soreness decreases when wearing socks for recovery. A study has shown that long distance runners reported reduced muscle swelling and pain; high jumpers were able to reach their peak-vertical jump more quickly when wearing compression gear. Another study has shown that cyclists wearing compression tights were able to perform better on the second day of back to back 40k time trials compared to their counterparts with regular tights. The next week, the cyclists completed the same tests but switched tights and still found that those with compression tights seemed to recover faster. Scientists still don’t know exactly why this is the case, but there is a hypothesis that increased blood flow may help replenish glycogen stores more quickly. There have been other studies of athletes reporting less muscular damage when wearing compression for recovery or during hard races, allowing them to recover faster with less perceived muscular soreness.
So overall, it seems like there is no real correlation of a performance benefit, but there may be some benefits in recovery. Wearing compression gear may allow you to bounce back more quickly from a hard workout or race by lowering perceived muscle soreness (not a very scientific term, which is why studies are having a hard time figuring out the real mechanism). This will allow you to work out harder sooner or just help you be more comfortable the day after a hard workout. There definitely are no negative effects of compression gear, so it doesn’t hurt to try it out. I don’t really see myself going all out with tights or wearing compression gear during workouts—I already feel like it is sweltering enough on the track without adding knee-high black socks. But I definitely will continue wearing them for recovery. Just around the house though, not in public.