The question on the table is simple enough: does jumping into cold water suppress your testosterone? Dr. Reena Malik, a urologist, digs into the research and lands on a measured answer — probably not much, and probably not permanently. A 2019 study showed roughly a 10 percent dip in testosterone after cold immersion, while the control group saw a 9 percent rise. On the surface, that sounds alarming. Look closer, and the sample sizes are small and the difference is not statistically significant. That's the kind of nuance the internet tends to skip.
Here's where it gets interesting. We have another article in the database — Dr. Thomas on cold exposure and exercise sequencing — that points in almost the opposite direction. His finding: cold exposure *before* exercise can actually boost testosterone, and the order matters enormously. Cold after training may blunt the anabolic signal. Cold before training may amplify it. That's a completely different conclusion from the same practice, separated only by timing.
And then there's the neuroscience angle — a separate piece on cold showers and dopamine cites a neuroscientist claiming up to a 250 percent increase in dopamine from cold exposure, with testosterone following along. The rat studies in our database are less encouraging, showing prolonged cold exposure in non-adapted animals suppresses testosterone. But rats are not people, and "non-adapted" is doing a lot of work in that sentence.
Dr. Malik and the broader research community agree on this much: the acute, short-term testosterone dip is real but modest, and it recovers. Military studies confirm it — hormones drop under cold stress, then normalize during rest. What nobody has done yet is a long-term, properly powered study tracking testosterone across months of consistent cold immersion practice in adapted individuals. That study doesn't exist. Which means every confident claim in either direction is working from incomplete data.
Don't cold plunge immediately after strength training if testosterone optimization is your primary goal. That post-workout window is when you want your hormonal environment undisturbed. If you want the cold, do it in the morning before you train, or on recovery days when your anabolic signaling isn't in active competition with a stress response.
We have a paper in the knowledge base on exercise, testosterone, and cortisol showing significant increases in both hormones one week after repeated bouts of hard training. The surprising parallel: cortisol is rising alongside testosterone, not opposing it. The same pattern likely holds with cold exposure. A temporary cortisol spike from cold isn't evidence of harm — it's evidence of adaptation in progress. The question is never whether stress happened. It's whether recovery followed.