Training and muscle mass

33% does seem goofy. When I was 5' 6.5" 140# I was tested at 17% body fat. As a quick reference - do you easily float in the water or sink? 33% will not sink like a rock. Do you lift weights with low reps/heavy weights, or high reps/low weight? Can you do boy's pushups, chinups, pullups, dips? Bodyfat tests can also be misleading depending on how hydrated you are, what you had for recent meals (beans?).

I disagree with gbrain's estimate of weight. I weigh much more than 105lbs and I have a very low body fat for a women. Weight: 125lbs Body Fat %: 33% Lean Weight Percentage: 67% Lean Weight: 83.75lbs Goal Body Fat %: 20% Goal Lean Weight %: 80% Goal Weight = Lean Weight / Goal Lean Weight % Goal Weight: 104.6875 What this means is not that 105 is a good weight for Marcia. What it means is 33% body fat is wrong unless Marcia is very fined boned with almost no muscle, because at 5'6.5" 105lbs is still incredibly light. IF the bodypod results are accurate, 105 is a healthy weight for Marcia. 20% bodyfat is in the middle of the fit and athlete ranges for a female.

I think I understand. You are saying that because the measurement is inaccurate it is calculating that she should weigh 105 with a 20 percent body fat.

I think I understand. You are saying that because the measurement is inaccurate it is calculating that she should weigh 105 with a 20 percent body fat. Right. 20% is a health body fat percentage, but would 105lbs be a healthy weight for someone 5'6.5"? Those people exist, but they are less common.

Hair and clothing, and operator error skew bod pod results.

That does seem high given your stats. Do you look or feel fat? If not, the body pod could be the problem, and if that number if going to bother you, go get another test to cross check. The principle behind the bodypod is sound, but the execution faces a lot of challenges. For example, if you took the test while running a fever, that could throw the results off. There are lots of seemingly simple things that can throw off the results. You could be at 33% body fat even with your high activity levels. Neither swimming nor lifting weights encourage lean bodies. But I am leaning toward your results being wrong. At 5'6", at 20% body fat, which is pretty lean for a female, your weight would be around 105. You would have to be very fine boned and lightly muscled for that to be realistic. If the number is going to bother you: Skin fold calipers in the hands of an expert are just as accurate as bodypod with less possible causes for error. Underwater weighing is probably the most reliable if you have access to someplace.

33% fat! 42 pounds of fat out of your 125 pounds! The 'bod pod' must be wrong.

Other than human error, your age,diet, and genetics are all an issue. \ I disagree with gbrain's estimate of weight. I weigh much more than 105lbs and I have a very low body fat for a women. I honestly feel like numbers are not the best thing to judge a body on. women also can have a lot of hidden fat inbetween organs making their percentage higher than what they actually look like. If you are really worried about the numbers,- maybe you are concerned about health? I guess understanding where this concern is coming from would help too. I would repeat the test as well as getting the calipers and the handheld one done. If the numbers are still high and you want to lower them, I would suggest changing your diet.