Caffeine and click speed

[Shadow Trader]

A third coffee before the London open feels productive. Heart rate up, reactions quick, thoughts sharp. For the first hour, it might be true.

The trade-off shows up later. Caffeine increases arousal, which helps with simple fast tasks and hurts with complex judgment. A scalper that has to decide quickly and stay calm may find the jitters push toward impulsive entries and early exits.

Hands matter as well. A slight tremor makes mouse precision worse, which matters when clicking on a small button in a fast market. Missed clicks, misplaced orders and double clicks increase.

The pattern differs from person to person. Some do best with a single cup, others with none. The only way to know is to track it: note caffeine intake and compare it with the day's results and the number of execution errors.

A few days of careful notes is all it takes. If errors rise after the third coffee, there's the answer.

Timing also plays a role. Caffeine's half-life is around 5 to 6 hours. A cup in the afternoon can affect sleep that night, and poor sleep affects the next day's session more than any coffee.

How many cups does it take before performance starts to slip?

[Amanhasnoname]

For me it is one cup, and the second is where things start to slip. I tracked it for about a month because I suspected the coffee was behind my sloppy entries at the London open, and the notes were pretty clear. On two coffee mornings I had more misclicks and more trades closed early for no reason I could explain afterwards.

The jittery hands bit is real. I trade with a mouse and on a couple of occasions I clicked sell when I meant to move the chart. Since then I use keyboard shortcuts for orders, which helped regardless of caffeine, but the coffee clearly made the problem worse.

I now have one cup about an hour before the session and switch to water after that. The bigger surprise was sleep. When I stopped having coffee after lunch I slept better, and the next morning's trading improved more than anything I'd changed on the charts.