Cold water immersion benefits are not backed by quality science, report says | CNN:

A systematic review of scientific studies on the Wim Hof method of cold water therapy found the quality of the research inadequate to support most claims of effectiveness without addition investigation.

Wim Hof, a Dutch extreme athlete and motivational speaker, is well-known for his ability to withstand the cold.

“It must be noted that the quality of the studies is very low, meaning that all the results must be interpreted with caution,” according to the analysis published Wednesday in the journal PLOS One.

Hof attributes his success to his training method, which focuses on a commitment to practicing cold water therapy with a specific form of breathing. The training reduces stress, improves sleep, bolsters the immune system, and increases energy, focus and willpower, according to Hof.

While some research did hint at “promising” anti-inflammatory effects from a combination of cold water immersion and the Wim Hof method of breathing, “more research of higher quality” would be needed to verify that finding, the researchers noted.

I’ve started ending my morning showers with a one-minute cold shower. For whatever reason, after about 20 seconds my low back completely loosens up and I feel invigorated. I suspect it’s the cold water shock causing my body to dump adrenaline, but I don’t know.

What I do know is that it’s worked for me repeatedly on a daily basis now for several months. I wouldn’t claim, especially with a sample size of one, that it’s reducing stress, improving sleep, bolstering my immune system, or increasing my energy, focus, or willpower. But it definitely makes a difference to me, and I have no plans to discontinue it. 

It’s not a fun experience, but for me it’s worth it, and I would suggest that it may be worth it for you as well.