Strength training - important or not?

If you are doing "traditional" strength training, then HRM calorie numbers are not accurate--the elevated HR during strength training is not the same as during cardio and doesn't indicate the same level of caloric burn.

Please explain. What you mean by "traditional" strength training (I'm assuming, weight training, not just resistance training), as well as the why. How is it different to elevate heart rate by walking at a brisk pace or by doing lunges and squats?

The different energy systems each require a different bloodflow for a given output. Cardio exercise uses mostly your aerobic glycogen and fat systems, that require a high heart rate for a given energy output. Heavy strength training uses primarily the creatine-phosphate and anaerobic glycogen systems, which don't require as much blood flow to recharge (the glycogen and C-P is stored nearby, in the muscles), and don't require oxygen as part of the reaction, so no lung to muscle transport is required.

The anaerobic glycogen system is a very inefficient reaction, the body uses a lot of glycogen for a little energy, and then has to clean up the toxic byproducts (lactic acid). But because it doesn't need to wait for the oxygen via the heart, it can sustain a much higher output in short bursts.

Heart rate monitors are good for estimating calorie burn for the aerobic systems, not so much for the calorie burns for the anaerobic systems. When doing cadio the energy contribution from the anaerobic systems is minimal. The vice versa is true for heavy strength training, where the vast majoirty of ATP is produced from anaerobic pathways.

Thank you! No time for a detailed response, so I'll ask more questions.

So, in a (purely hypothetical) situation where someone is doing lunges or squats for 60 minutes and getting their HR up, that strictly (or to a substantial extent) only uses the anaerobic pathway? Or does this apply only to the high resistance/low reps sort of workout?

It's not really an "on/off" "either/or" system, and there are plenty of variables. In general, it might help to think of the activities as lying on a continuum--the greater the resistive component, the less the aerobic, and vice versa. Just as heavy lifting has little direct aerobic effect, aerobic exercises like running, cycling don't provide much in the way of resistance training.

The effect can also be affected by conditioning and training status. An untrained individual who does nothing but heavy lifting will see a modest increase in aerobic conditioning--if for no other reason than the fluxes in blood flow caused by work/recovery will mimic an aerobic training effect. However this is probably not going to be sustained. Conversely, an untrained person starting a cardio program will see statisically significant increases in muscle strength (and perhaps even small increases in mass). However this occurs only in response to the initial adaptation to the specific muscular demands of the cardio activity and will plateau fairly quickly.

Based on what most of you are saying, people that are not actually doing weight lifting (heavy weights, low reps) are not involving the anaerobic pathway. People mean different things when they say strength training/resistance training. It could be weight lifting, it could be the seemingly more popular lower weights, higher reps approach. If I'm reading this correctly, the former involves the anaerobic pathway, and the burn cannot be accurately measured by HRMs, while the latter recruits less of the anaerobic pathway, and the caloric expenditure is more accurately by a HRM.

You are essentially correct in your assumptions. Just to be clear though, low weight, higher reps is muscle endurance training. Not that different from cardio. For it to be true STRENGTH training it would involve improving your strength. This mean lower reps, 6 or less, and higher weight. Strength training does not build mass. It just improves strength... oh yeah, and burn fat like crazy!

Based on what most of you are saying, people that are not actually doing weight lifting (heavy weights, low reps) are not involving the anaerobic pathway. People mean different things when they say strength training/resistance training. It could be weight lifting, it could be the seemingly more popular lower weights, higher reps approach. If I'm reading this correctly, the former involves the anaerobic pathway, and the burn cannot be accurately measured by HRMs, while the latter recruits less of the anaerobic pathway, and the caloric expenditure is more accurately by a HRM.

You are essentially correct in your assumptions. Just to be clear though, low weight, higher reps is muscle endurance training. Not that different from cardio. For it to be true STRENGTH training it would involve improving your strength. This mean lower reps, 6 or less, and higher weight. Strength training does not build mass. It just improves strength... oh yeah, and burn fat like crazy!

In all fairness, muscle endurance training would also improve strength over the long run. Otherwise, people wouldn't go up in weights. Obviously, it isn't the most efficient way to go about it.

Circuit training combines the best of both worlds. Get your heart rate up in the fat burning zone as you lift.

Edward

I strongly encourage you to get a HRM!!!! You will be surprise at the amount of calories you are burning by lifting weights!!! Also add cardio to your workouts and limit weight lifting to three days a week. Beware, the scale will not always move on a weekly basis but (the scale) will eventually catch up with your progress. In a nutshell, lift the iron!!! MFP has it wrong on the amount of calories burned when lifting weights.....Hope this helps and encourage you to continue lifting IRON!!! Best of luck.

Like everyone here, I am trying to lose weight.
I did about an hour and 20 minutes of weight training this morning.
But when I logged it, along with walking my dog for 30 minutes, I only burned about 123 calories.
I am just wondering if I should forget about strength training for now and focus entirely on doing cardio workouts as they burn more alot more calories than strength training.
But then I hear that strength training is really important as it helps build muscle that burn calories long after cardio does.
I am not sure what to do. I want to get the best bang for my buck so to speak.

Anyone have any thoughts?

Its all relative......It's less important than breathing and eating right......And more important than about anything else you are doing.

Like everyone here, I am trying to lose weight.
I did about an hour and 20 minutes of weight training this morning.
But when I logged it, along with walking my dog for 30 minutes, I only burned about 123 calories.
I am just wondering if I should forget about strength training for now and focus entirely on doing cardio workouts as they burn more alot more calories than strength training.
But then I hear that strength training is really important as it helps build muscle that burn calories long after cardio does.
I am not sure what to do. I want to get the best bang for my buck so to speak.

Anyone have any thoughts?

I use circuit training caloric values on MFP for the time I lift weights and reduce it by 50%. Seems to work for me. Credit for the training calories and not overdoing the presumed burn.

You can use something like this to estimate the calorie burn http://www.caloriesperhour.com/index_burn.php

i use this site its awesome

I have constantly remind everyone that I am not saying that resistance training does not burn calories, nor am I saying that resistance training is not important for weight loss. While obese beginners can lose significant weight doing cardio alone and even maintain lean mass (independent of structural reductions because their bodies are becoming smaller) for sustained and permanent weight loss, I feel the resistance training is crucial. Not only that, it is essential for long-term health and quality of life.

My main position in these discussions is that you can't use an HRM to estimate calories and database values aren't much good either.

Here is one study that illustrates the problem. It's an older one, but it is relatively simple to read.

http://www.ncbi.nlm.nih.gov/pubmed/2072844

The relationship between heart rate and oxygen rate is the most important component for an HRMs to accurately estimate calories. That's because heart rate, by itself, has little significance. Heart rate is only useful as an indirect indicator of oxygen uptake.

The algorithms built into most HRMs have been developed and validated by comparing them to actual oxygen uptake measured during aerobic exercise. Steady-state aerobic exercise.

During other activities and at higher intensities, there is a different "scale" between heart rate and oxygen uptake. But the HRM doesn't know the difference, so it can only return estimated data according to how it's programmed--when it senses a heart rate, it estimates oxygen uptake (and calories) as though you were doing steady state aerobic exercise.

In the study I cited, during moderate resistance exercise, for a given heart rate (percentage of HR max), the actual oxygen uptake was only about 1/2 the amount which occurred when performing steady state aerobic exercise at the same heart rate level.

Cardio burns the fat. Lifting shapes the muscle under the fat so you look better. It also increases your metabolism. Say you weigh 150 lbs. If that's with 22% body fat you will look slimmer and shapelier (and hotter!) than if you are the same weight but 30% body fat. You will also be able to eat higher calories and maintain! It's easy to fall into the trap of looking for the best calorie return - the best bang for you buck - in exercise, but some of the best barely even register on this site because they aren't really cardio. It's okay. Do both.