Gaining 6lbs in 2 weeks

Sodium and Water....

You only gain about 1 pound of muscle a month (per body builders that I know). Take your measurements....Its the only true indicator.

Have you been measuring yourself? I lost 2 lbs in 2 weeks and then gained it all back, but I didn't gain back ANY inches. I find measuring myself a much better gauge than the scale.

Ehte when you work muscle hard it causes tiny micro tears; the mucles then 'hold on' to lots of water whilst they repair these tears. Especially if you're quite muscly already this can mean A LOT of water retention - and I know that you've been doing a lot of hard work lately! I'm guessing that your clothes may be telling you what your scales are not - you are burning fat, but your muscles are hanging on to that water! Have you taken a rest day lately? If not, give yourself a day off, make sure you drink plenty of water - and within a couple of days I'm guessing you'll see a sudden shift in those scales! The others are right - go by the tape measure - it doesn't lie! You can of course also be gaining muscle on top of retaining water, though it does take a bit longer to build muscle. Keep at it, you're doing really well!

One other note, I know that you are fasting at the moment which is going to be doing all manner of strange things to your body! Be kind to yourself at this time - I wouldn't think any high cardio work would be a good idea whilst you're fasting (I've had people faint in front of me at TaeKwon-Do because they haven't eat yet, not good!) so if you're still going to exercise whilst fasting keep it to low fat burning!