I started CT's "Get Jacked...FAST" 11 days ago.
Programs diet is very low carb
I added L-Leucine in on day 3 (first time user) and got a massive headache during squats. It was so bad, I had to wait 10 minute before attempting another set.
It slightly diminished throughout the workout, but I could feel the ache late into the evening.
This severe headache has reoccurred several times, and seems to be brought on the quickest when I'm fully exerting myself, which of course is killing my intensity.
One even occurred during an orgasm.
I found nothing relating l-leucine to headaches, and did read a bit on "carb withdrawl" headaches, but mine ONLY occur when I'm lifting.