While I'm on the topic of jobs, one of my new gigs for 2011 includes administering exercise/metabolic tests -- ya know, get on a treadmill or bike and work your ass off until you reach your maximum while us science nerds record lots of data. If you've done this before, you know they're short in duration, but they hurt like a mother %^&*@. The pain is well worth it, though, because your training becomes that much more specific to YOU. It doesn't matter if you're novice or elite, the info is invaluable--you'll find out your metabolic efficiency, VO2max, lactate threshold, heart rate zones that correlate with all that, etc.
On top of the max test, we record lots of the basics--perfect for further establishing that baseline, setting goals and for re-testing later. Among the data: a full blood profile (are you low in iron, etc?), resting heart rate, blood pressure, weight, height and *gasp* body fat!
Oh yes, beloved body fat!
Measuring body fat percentage is a quick, easy process and not to be feared. Only fear the test if you have a rookie using the calipers and he pinches you wrong leading to an instant bruise (yea, I was the bruisee lol).
I had my BF taken last week (by a pro, not the rookie haha), and low and behold I'm at 16%. That's low. Not the lowest of lows, but low. However, it's actually fairly normal for a female athlete--depending on the sport of course. You'll see elite female long-distance runners way lower than me. Actually, the doctor I work with, Dr. Falsetti, says he likes to have his triathletes, particularly long-course racers, have a little more meat on them instead of getting to the bare-minimum body fat for several reasons.
--- Speaking of bare minimums...
The lowest essential body fat percentage:
According Sports Nutrition by Asker JeukendrupMen: 3% Women: 12%
According to The American Council on ExerciseMen: 2% - 5% Women: 8% - 12%
--- Knowing the lows, here are some more numbers for ya...
Normal BF ranges for average young people (essential + storage fat):
According to the Sports Nutrition textMen: 12% - 15% Women: 25% - 28%
Normal BF ranges for athletes:
According to the NSCAMen: <7% - 17% Women: <15% - 25% . According to ACE: Men: 6% - 13% Women: 14% - 20%
PRO TRIATHLETES according to Matt Fitzgerald's Racing WeightMen: 6% - 10% Women: 12% - 16%
Note that there are big ranges in athletes because the sport makes a big difference: You'll see the lowest in XC, gymnastics, bodybuilding, etc, and higher BF in sports like football, shot put, softball, etc.
Why are Women Fatter?
Men can get a lot lower than women. That's obvious. For women, a whole slew of issues may accompany super low body fat--hormonal issues, decreased bone density and, of course, lack of menstruation, or amenorrhea, defined as at least three months without a period. Chances of amenorrhea increase greatly if you're an athlete under intense training--you can pretty much say goodbye to "that time of month." Women just need more fat than men to sustain normal function. Period. (No pun intended.)
Take me for example. I'll be honest with you guys... I've had issues with my period and its regularity even before I was a triathlete, so when I became a triathlete and my BF inevitably decreased, my period disappeared. I know I'm not alone here. Shoot, I look "big" if I stand next to a Chrissie Wellington or any female of that caliber :) But, I've been actively working on this issue for years now rather than ignoring it... lack of menstruation is not a gift to save you from the hassle of periods. As a result, I'm proud to say I got my period again and have been regular for more than a year now, but I'm tweaking some things so we'll see what happens... more on that to come. And no, by tweaking things, I don't mean I'm trying to get more lean! Heck no!
So what's my point with all this?
I guess it's to stress the importance of getting in tune with your body--male or female. As an athlete, I stress this even more! Athletes should go a step further than the average person and get an exercise test with all the bells and whistles of body comp, etc. This day in age no doubt you hear the term "metabolic efficiency" floating around. That's nothing new--it's just being exposed and explained to more people now, which I think is fabulous! That info shouldn't be exclusive to exercise scientists and coaches.
Bottom line: If you're going to be an athlete, triathlete or whatever, you should know every detail about your body from VO2max to body fat to iron levels. It will help keep you healthy and make you faster!
Body Fat Charts
I'll leave you with some body fat charts I have from the National Strength and Conditioning Association (NSCA), from which I hold my certification as a Strength & Conditioning Specialist (CSCS). Additionally, another great resource on body fat and all the charts, specifically geared toward endurance athletes, is Racing Weight by Matt Fitzgerald. Great book overall, actually :)
The top row is sex/age, then go down from there to see body fat percentages and their classification from lean to overfat (aka obese). Of course, you have to go to a professional to get your BF percent--the common method is taking skinfold measurements with calipers and using an equation to find the percentage--but once you do that, you can see what range your body fat is in and set appropriate goals... Take charge of your health and fitness! It's a worthy investment in YOU.