rough start? flawed tools? or no problem?

I started 2 months ago at 183 (before that I was eating good food, but too much - and exercising sporatically)  the first month I decreased the amount of food and increased activity slightly (yoga 4-5 times per week)  and dropped to 177 the second month, I joined a gym and since then have done 40-180 minutes of cardio (mostly low intensity and long duration: swimming, elliptical, jogging, cycling)  5-6 times per week and weight training 3 times per week with 3-4 yoga sessions thrown in.  Trying to eat around 1800 but have struggled with consistancy (tending to eat less rather then more)  At the end of the first month, I was down to 171 - which is exactly the pace I was looking for.  However, when I did the free monthly body comp anaylsis at my gym, the print out said all 6 pounds I lost were muscle mass.  The gym staff said that maybe I wasn't lifting enough weight - but I've seen an obvious increase in the amount I am able to lift - and I certainly feel stronger (not to mention having to use safety pins to keep my pants up).  While my fat mass is too high, my muscle mass is higher than normal as well - so losing some muscle mass is not a major concern for me.  But I am concerned that 100% of the loss was from muscle...  assuming this machine is accurate.        

Not looking for a definitive answer or anything, but maybe some advice if you've been in the same situation. 

Wow, surprised you haven't gotten responses already...

First and foremost, the body fat analysis done at a gym can vary widely in accuracy - it all depends on the consistency of the person taking the measurement, so it's entirely possible that you didn't lose just lean mass.

That said, however, I'm a bit confused by your workouts.  You do 40-180 minutes of cardio a DAY?  Did I read that right?  Plus yoga and lifting several days?  If that's true, that's insane.  It sounds like more free time than I even have!  I'm also curious what weight lifting you're doing - free weights and following a program, or machines and somewhat random, or something in between? 

This is one of the most helpful articles (IMO) often linked to on CC.  Basically, for fat loss you want to lift heavy weights for ~3 hours a week, throw in some HIIT, and then with any leftover time, add in high and then low intensity steady-state cardio...in addition to eating a clean, healthy diet.  Your routine seems to be primarily low intensity steady-state cardio.  I'm not saying that this isn't good for burning calories/weight loss and general health, but if you are looking to lose fat, you may want to switch up your routine.  Also, if you're doing the amount of exercise I think you're doing, you're probably not eating enough.  I eat 1700 at 166 lbs and only exercise 3-5 hours a week total, including 2-3 of weight lifting. 

I hope you'll give that article a read and then reevaluate your routine.  What you're doing isn't bad, but it could be better! 

Hey thanks much for the response.  You're right, it sounds like a lot of cardio, but I commute to work by bicycle so that's a consistant 40-60 minutes every day plus whatever I do at the gym.  I get up to 180 minutes if I take a little bike trip or read on the stationary bike.  the yoga is hatha, so basically a glorified stretch after working out.  the weights are machines but following a basic program. 

will try eating more and substituting some high intensity cardio.

Oh, I see!  Jealous...wish it was feasible to ride my bike to work...

Good luck with the changes, hope you will see even better results!