Yeah, you lose strength at first, but by the time you are two weeks into the diet it returns. I'm 10 days into mine, and today I strength is back. I've handle the same poundages I did at 225 ibs, but was down to 212 ibs yesterday, today was a carb up day for me so by the time I weighed in I was back at 217, none-the-less at 8 ibs lighter I'm at 100% strength. If you're strength is down you are probably not eating enough fat. Just my 2 cc's.