Critique my weight loss formulas?

Hi -

I’ve been trying to lose weight and decided to get organized and really figure out what the numbers are that I’m working with. I’m a 51 yo male, 200 lbs, 5’ 7". I’ve started exercising every day (for a month now) on a stationary bike throughout the day (I work from home), and I’ve been trying to measure my exercise calories vs my needed calories to work toward a consistent deficit every day. Today I made a spreadsheet to track all this and would appreciate your input.

Here’s my assumptions:

My calories needed every day are my BMR plus exercise calories. My BMR from here is 1800ish kcal/day for my height/weight/age. I’ve been trying to do 60-90 stationary bike minutes per day in sets of 15-20 minutes. When I do so, my heart rate is between 120-130bpm according to the stationary bike (no idea how well bikes measure), so according to this page, 60 minutes of exercise at 120 bpm is 702 kcal, or 11.1ish kcal/min. Since I’m doing bike sets in increments, I’ve chosen 120bpm as the calculation amount even though my heart rate is generally higher, because I realize that doing shorter sets means my heart starts at rest at the beginning of each set.

So here’s today’s calculations:

Bike minutes: 75   833 kcal
BMR:               1800 kcal

Food               1440 kcal

Surplus/Deficit:  -1193 kcal
Deficit %          45%


  1. Food calories includes alcohol (I had 12oz of wine today @ 288kcal).
  2. I realize a 45% deficit is way too high to stick to. I figure a 30% deficit isn’t a bad daily deficit, but I’m still feeling my way toward a diet plan in that range, and I’ll probably have a duly logged snack before bed tonight. :slight_smile:

Anyway: are my assumptions reasonable, re base calories + exercise vs food calories, vs whatever? Does my math work, does it all add up, are there any holes, and do you have suggestions?

Can someone comment on this? I’m in a similar boat/bike/elliptical, in that I work from home and don’t always have an hour+ block to devote to cardio. If I (or squeegee) put in four to six 15-minute blocks throughout the day, is that the same as going for an hour to an hour and a half jaunt? Assume that we have fairly reliable heart rate information and that the fifteen minute blocks start when heart rate reaches between 70 and 80 percent of max.

BTW Squeegee, if it’s at all in your budget, get a basic heart rate monitor. From what I understand, exercise machine-based pulse detectors (the kind with the handles) are notoriously inaccurate. My limited experience with two different machines (treadmill and elliptical) bears that out—my basic Polar HRM is as accurate as stopping to count manually.

The single best too I got to help with weight loss is a bathroom scale.

I was shocked to learn how cheap they are. When I was younger, the were big and bulky and very heavy and cost around $50 (which is at least $200 today).

But I got the most beautiful and elegant scale at Walmart for $18. It is almost paper thin. Truly unbelievable.

Having that scale and weighing myself periodically is a great way to see the cause and effect of eating certain foods and exercising. It has provided me with a huge incentive to lose weight and I am very happy with my progress.

I’m guessing you both have scales. But if you don’t, considering the cost, that would be the very first thing I would get.

Good luck to both of you.

You’re underestimating your caloric needs. Your BMR is the calories consumed while your body is at rest. It’s what your body needs to keep you warm and keep your organs functioning. It’s not going to be accurate unless you spend all your time off the bike sleeping or laying on the couch.

You can use this calculator to get a better estimate of your caloric needs. I assume that most of your waking hours are at least “very light activity”.

I use a couple of different stationary bikes at the YMCA and wear a heart rate monitor. I’ve noticed little difference between my HR watch and using the HR monitor on the bike either with or without the hands on the grips.

BTW: Some machines, such as Lifecycles, can read the heart rate straps and have exercise programs based on HR. However you need a cheaper heart rate strap to work. I have a fancy Garmin bicycle computer with an Ant+ capable strap. It doesn’t work on the Lifecycle. However a cheap Polar strap will.

One thing I’ve noticed about stationary bikes is that they often wildly overestimate the number of miles and sometimes calories burned.

I’ve also noticed that some HR monitors wildly overestimate the number of calories burned. I have both Garmin Forerunner 305 and Garmin Edge 705 GPS devices for running and cycling. There’s just no way that I’m burning as many calories as they say. Others on Garmin forums agree. Therefore I put in 50 lbs less in my profile to get back into the ballpark. I had similar issues with a Polar HR monitor.

Back to the OP. Cutting too many calories can be counter productive. You could start starving yourself and your body can start consuming more muscle mass for food. You may lose weight, but not be healthier. A longer approach to your goals might be better.

Counting calories is difficult. Most people underestimate how many they consume, but other people might go to far in the other direction.

Calorie burned results from machines or on-line calculators are also inaccurate. So between not knowing exactly how many calories you are taking in and how many that you are actually burning, you results could be all over the place.

One device doesn’t lie: a scale. Well unless it’s defective. However fluctuation from day to day is normal. Just being slightly dehydrated can make a 4 lb difference.

My suggestion is to find an exercise routine that you enjoy. I use stationary bikes in bad weather and I don’t really enjoy it. However I know that it will improve my cycling performance once the weather gets better and I really like riding outdoors.

Well without knowing what you are eating it’s hard to draw any conclusions. Dieting or increasing your exercise load has a slim chance of working in the long term if you are relying on mathematics to solve a biological problem.

Here’s a simple way to become fit:

  • drink water or tea only: lots of it, with no sugar;
  • quit eating sweets or junk food;
  • exercise an hour a day (power walking is enough);
  • quit eating bread for three months;
  • replace red meat with fish in your diet for six months;
  • eat a wide range of fruit, vegetables, nuts, and seeds;
  • have five/six meals a day, a meal every three hours;
  • do not eat anything after 7/8pm.
    Nothing else is required. In six months you may lose 20 kilos. Continue with a healthy died and you’ll be fine.

I concur.

OP. As a 200 pound male, you are looking at 2800-3500 calories a day for your basic routine. Adding the the exercise (which sounds like a very good plan), you are going to add 800-1500 calories a day.

**Eating only 1400 calories a day, you are either going to pass out (or resort to sneaking donuts!). **

You need to replenish the vitamins and protein consumed during a workout and other daily activities; your body cannot synthesize all it nutrient needs from excess body fat. A better idea would be to plan out a diet rich in vegetables, light protein, and fiber to meet your daily caloric and nutrition needs, leaving a perhaps a gap of 500 calories at most (less than a 10% deficit). If you feed your body right, exercise will not be direly exhausting, and you will eventually be able to enjoy it!

Weight loss really should be a secondary concern to developing healthy habits. At a 500 calorie deficit, you will about loose a pound every two weeks, which is a very healthy and sustainable rate. Treat your body right, it will reach a better overall level of health!

ETA: Even breaking even calorie wise, the added exercise will improve your heart health, and encourage muscle growth, which can help reduce your percent body fat. Just be careful not to over exert yourself while you begin you routine!

Thanks, I’ll look into that.

Well, when I’m not on the bike, I’m generally still, either at a desk working or in a chair reading or watching TV. But that’s good advice. I went to that page and basically split the difference by doing 12 hours sleeping, 12 hours light activity per day, and got 2400 calories for my base. That doesn’t seem like a very unreasonable guess to me.

Yup, that’s why I’m going with heart rate times minutes. I don’t know a better way to estimate calorie consumption with the information I have.

Yup. That’s partly why I’m doing the math, so I don’t under or over diet. I didn’t mention this in the OP, but I’ve also been doing sets of basic exercises (pushups, situps) throughout the day. I’m not including those in my exercise calories because I don’t know how to count, say, 4 sets of 10 pushups per day, or so many crunches, etc, to try to minimize muscle loss from dieting.

I hear you. Right now I’m trying to be accurate by just eating prepared food (Weight Watchers, Lean Cuisine frozen meals) because that’s dead simple: the calories are on the label. I’ll supplement with stuff like carrot chips or steamed veggies, and I try to count it all as carefully as I can, e.g. so many ounces of this veggie equals so many calories.

See just above. I’m also not eating red meat at all and trying to find meatless meals to eat as I can. I’ve cut out most of the alcohol I’d been drinking and take a daily vitamin supplement.

What a ridiculous statement.

Huh. If I go to Fuzzy Dunlop’s calculation page, and input 24 hours/a day of “light” activity (no sleep! I get 2717 calories. Seriously, I sit on my ass all day unless I’m doing the bike exercise in the OP plus my (really really minor) calisthenics I mentioned in my previous reply.

Agree. I’m trying to find the balance. FWIW, I finished yesterday at 1900 calories.

I found this calculator better than most and was able to keep up a 500 or so calorie deficit a day for the 2 years needed to halve my weight with little trouble. Slow and steady. Swing some soup cans around when you are on the bike to add a little upper body muscle and keep your metabolism ticking over. The trouble with bigger deficits is that your body will take muscle as well as fat to fuel itself and muscle is metabolism. You can get slim but what you want is to be lean. I fell in love with weight training at some point and now my little body needs more food than ever before just to get through a day. I like food.

It’s completely ridiculous. You can’t expect your weight to perfectly track your predictions but you’ve said nothing at all to indicate you expect it to. If you weigh yourself once a week and are honest about what you’re eating / exercising, after a month or so you’ll have a good idea whether your predictions are on track.

I worked a medical doctor once who only works on weight loss (bariatrician) and we figured out my caloric needs using math too. I’ve never heard this ridiculous idea that biology somehow defies math.

This approach has more floors than the Empire State building.

I wish you well but it’s not going to happen.

Join a running club: go crazy - meet and talk with people instead of a spreadsheet.

Well, thanks for the threadshit.

I’m a 51 year old, 200 pound man with arthritic feet. Walking hurts, so a bike (indoor for now) is what I have to work with.

Why don’t you join something like My Fitness Pal and have their program do all this for free for you? Much simpler.

Nice, I like that page. And congrats on the big weight loss.

Yup. I’m doing my situps/pushups to fight muscle loss; I figure the leg muscles are covered with bike usage. I’ve also cut out as much fat as possible in my diet. Lean lean lean.

Yup, and sadly it likes me back. :slight_smile:

Never heard of it, that’s why. I’m looking at the page now, thanks!

… hmm, I told it my specs (height, weight, age) that I want to lose 2 pounds a week (probably ambitious, but I’m just playing with the site) and that I want to exercise 60 minutes a day, 7 days a week. And… it says I can eat 1200 calories a day with that regimen. :dubious: I must be missing something in how to use it. I’ll play more.

Don’t set it at 2 lbs. a week. I set mine at one lbs. a week and it sets me at 1440 net calories a day (female, 5’7", 145 lbs.).

Keep in mind that the calories are NET. So, any exercise calories you burn, you eat back. So if you are set at 1400 net, and burn off 600 calories with exercise, you eat 2000 calories that day.

ETA: And check out the Community. There are lots of very knowledgable people that can help you with these questions there.

I borrowed a heart rate monitor from the wife (I had no idea she had one until I mentioned I was interested) and did 20 minutes on the bike with it. That monitor largely agrees with the bike’s heart display, although the bike’s rate tends to jitter around a bit more, which is what I’d expect. So, yeah, I really am doing between 120 and 130 when I ride (after some startup minutes per set).