Wow, there's a lot of confusion about calorie calculations on this thread...so here's a clear, concise explanation.
BMR = Basal Metabolic Rate. This is the amount of calories your body would burn over a 24-hour period if you remained at rest - i.e. a coma - all day long. BMR, by itself, does NOT take other activities into account. There are several formulas to figure out BMR, including:
Harris-Benedict Formula: 66 + 13.7 * (mass in kg) + 5 * (height in inches) * 2.54 - 6.8 * (age in years)
Katch-McCardle Formula: 370 + 21.6 * (lean body mass in kg)
Remember, kids, 1 lb = 0.45359237 kilograms (alternatively, 1 kg = 2.20462262 lb)
Most people (myself included) prefer Katch-McCardle if you can get accurate body fat estimates.
To Calculate Calories Burned
Cals burned = BMR * Activity Factor
Activity factors: (stolen from
http://www.shapefit.com/basal-metabolic-rate.html)
Sedentary = BMR X 1.2 (little or no exercise, desk job)
Lightly active = BMR X 1.375 (light exercise/sports 1-3 days/wk)
Mod. active = BMR X 1.55 (moderate exercise/sports 3-5 days/wk)
Very active = BMR X 1.725 (hard exercise/sports 6-7 days/wk)
Extr. active = BMR X 1.9 (hard daily exercise/sports & physical job or 2X day training, i.e marathon, contest etc.)
I run 12-16 miles per week and lift 3x per week; I use an activity factor of 1.65 and it is spot on for me.
To Calculate Ideal Calories Eaten
You can drop 500 cals per day to average 1lb/week of fat loss. BUT this isn't always ideal - especially if you have LOTS of fat to lose or you're already pretty small (women in particular). MUCH preferred is what I call a "Fat Loss Modifier".
Fat Loss Modifier = 0.8 is a great starting point; this is solid, steady progress and should be safe, allowing you to retain all of your lean mass.
Fat Loss Modifier = 0.7 is much more aggressive. You will lose faster, but you also risk losing lean mass (risk is less with greater fat amounts)
Example
At 6'3", 199lb, 17% BF my BMR (Katch-McCardle) is 1988.
To get cals burned: BMR * activity factor of 1.65 = 3281 cals per day.
Now, my chosen Fat Loss Modifier is 0.75; moderately aggressive. When I get below 12-13%, I'm going to scale it back to 0.8. BUT for now,
Ideal Cals eaten = Cals Burned * Fat Loss Modifier = 3281 * 0.75 = 2460.
How much fat should I lose with this diet? 3281 - 2460 = 821 cals per day. 821 cals/day * 7 days/week *1lb/3500 cals = 1.64 lb /week.
Guess what my results have been the last 6 weeks? An average loss of 1.6lb of fat.
Hope this helps,
Dave
Edit: Credit for the "fat loss modifier" goes to Tom Venuto, though he calls it something different. Heck, credit for just about everything I know about fat loss goes to Tom Venuto. If you haven't already, buy his "Burn the Fat, Feed the Muscle" ebook. Worth every penny.
AND
FOR THE RECORD
NO guy should be eating only 1400 cals per day. In fact, almost no girl should be eating 1400 cals per day.
1400 cals per day, with your activity, ends up being a roughly 1500cal/day deficit. (A little more, actually). This should be 3lb per week.
What? You're not losing 3lb of fat per week? Now we see the negatives of a very low calorie diet: your metabolism has adjusted downward, meaning you burn fewer calories than you should....which makes fat loss REALLY difficult.
Not to mention that the moment you lose your dedication and splurge, all those extra calories aren't used effectively and are stored as fat. This is why yo-yo dieters have such difficult times.
And if you are losing 3lb/week and you're not clinically obese, I hate to break it to ya but you're losing muscle here (unless you have radically superior genetics. In which case...you must have done a real number on yourself to end up fat to begin with). Less muscle = lower metabolism = less fat burned = more calorie reductions to maintain progress = less muscle and the cycle continues.
Again, I hope that helps
Dave
I'll also quickly add my experience.
Started out at 260lb, 33% body fat on a 1700cal diet. Lost a lot of weight quickly. Thankfully, I still didn't lose it too fast (rarely more than 2-3lb per week) so my lean losses were minimized. (The ONE benefit of being really fat).
But eventually, around 24% body fat, I plateaued. It's like my losses just stopped in mid-stride. I started to lose motivation, stopped working as hard or eating as clean, and kinda let things slide for 2 months.
Those two months were actually helpful, as they served as a "pseudo-refeed" and allowed my metabolism to slowly creep up to where it should've been. Since then, I've wisened up, changed my calorie intake to ~2450 each week (although after the occasional cheat meal, I've been roughly 100cals over on average). Guess what? I'm still losing, steady as she goes, averaging 0.68% body fat per week.
What's even better is that if I hit a plateau, I still have a little bit of room (not much) to drop calories for that final push. At 1700 calories, I tried to go lower...but my body wouldn't let me. Lepitin levels were all shot and the hunger pains were pretty tough to deal with.
Dave
P.S. Yes, I keep food logs...so I'm not just making these numbers up. It's sometimes tempting to go super-low-cal, but 99 times out of 100, it won't be as effective.
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