Cris LaBossiere

Cris LaBossiere
Strength training and mountain biking. My two favorites

Wednesday, January 6, 2010

Moms drop pounds with a four-minute workout - The Globe and Mail

Moms drop pounds with a four-minute workout - The Globe and Mail

Warning! Another armchair expert hacks an article on fat loss.

You can read in this (click link above) Globe and Mail article about a woman who had recently given birth dropped the last 10lbs of a 20lb 15 month postpartum weight gain by doing ultra intensive intervals for merely four minutes.


Apparently this is a new way of using athlete derived intense intervals referred to as “Tabata’s” (one set of 8 intense 20 second intervals with only 10 seconds rest between) to help mom’s lose body fat they gained through pregnancy.


Of course, this isn’t really possible, but since when do the facts matter? Hype up another implausible weight loss story and try to make it sound legit with some reference to science. I simply love the way this story turns out. Ah science. Quoting science can make people feel really smart. Misquote it though and you’re a slack jawed yokel.

Tabata intervals, which originated in the early 1990’s (and so are not actually “new”) offered no advantage to fat loss in this case, so it’s misleading to place the credit to the brief yet intense intervals.

Why?

Four minutes of interval training only burns off about 80 calories. That’s why. No matter what claims are made about fat burning or increased metabolism 80 calories just doesn’t cut it.

And no, there isn’t a special metabolic response to four minutes of hammering that results in hundreds of extra calories burned off after exercise; the elevated metabolism that has been measured post exercise only adds up to about 40 to 50 calories, and this is after longer bouts of intense exercise lasting 30 minutes or more, not 4 minutes.

It is true that this after effect, called EPOC: Excess Post-Exercise Oxygen Consumption is nearly double following intense exercise compared to easy exercise. The nugget of truth that is usually left out (on purpose) is that the doubling of oxygen consumption post exercise lasts mere minutes. Very quickly EPOC slides back down to nearly exactly what normal resting oxygen consumption rates are having not exercised.

Don’t be fooled by how this comparison is usually framed; “Burn 100% more calories after HIT (high intensity training) compared to low intensity training!  The time spent at this elevated rate is very short, it is in fact the amount of time you spend breathing hard after you stop.  Yep, that's it.  As your breathing rate returns to normal so does EPOC.  There is a tiny EPOC affect remaining after your breathing is back down to normal, but you're looking at 40 calories or so over a 24 hour period.  Yes, that is the total calories that EPOC burns, not even an oranges worth of calories.

Doesn’t sound as special when it’s explained this way compared to the “100% more calories burned!” con. Successful fat loss occurs when there is a calorie deficit of around 10 to 20% less than a persons daily intake requirements. On average that’s about a 500 to 800 calorie deficit per day.

You may think to yourself, ok fine, EPOC doesn’t really account for a lot of extra calories, but hey every little bit counts right? Maybe. I guess someone would have to study this in real life conditions, say measure the total caloric expenditure over 24 hours for people who workout hard compared to those who workout easy.  I am being totally facetious when I say that..

Here’s a nice bit of irony. Izumi Tabata, the internationally respected researcher who’s namesake is pinned to the now popular Tabata intervals, has also researched whether over a 24 hour period significant extra calories are burned via EPOC when a person trains hard or moderately.

Looking at a 24 hour period is more realistic as it measures the real life affect, if any, on fat loss, EPOC, and regular daily living, which includes eating. The result? No exercise group 2228 calories, moderate exercise group 2816 calories, and the HIT group 2813 calories expended for the day. No significant difference between the exercise groups, but of course the exercisers burned more calories than the non exercisers. EPOC did not contribute significantly to the total energy expenditure over 24 hrs.

Isn’t that wonderful? The goofballs that are misappropriating the purpose and confusing the methodology of the original Tabata interval protocol are also claiming it has extra fat loss benefits due to the EPOC effect.

In fact, Tabata himself was concerned about such claims, researched it and concluded there is no merit to such claims.  2816 calories were expended on a day with moderate exercise compared to 2813 calories for the day that had short intensive intervals.  The study conclusions were that the exercise was the significant contributor to total daily caloric expenditure and that the post exercise calorie expenditure  was insignificant.   Tabata abstract

Great for science, not so great for the untold number of people who fell for the yokels story in the Globe and Mail. It’s good to be able to write, but perhaps being able to read might also be an asset so you can check your facts first.

Here’s the details on Tabata intervals, if you’re interested

The purpose was to compare the effectiveness of steady state cardio to short intensive intervals

Results; short extremely intensive intervals increased aerobic and anaerobic capacity more than moderate intensity steady state over 6 weeks of exercise 5 to 6 days per week. Tabata abstract

The latest interval training; Proven by science!

Izumi Tabata et al submitted the research in 1994, it was accepted for publication in 1995. Anyone who presents Tabata intervals as the latest thing, or even relatively new, has overtly displayed their gross ignorance regarding the history of Tabata’s intervals.

This training protocol is over 18 years old! Get with the times all you charlatans who wax people with your BS claims of being in the know with the latest and greatest exercise.

The Tabata "protocol" reproduced an interval protocol used by the Japanese national speed skating team. Actually the credit for the interval protocol should go to Kouichi Irisawa, the coach who came up with idea and used the protocol for many years before Izumi Tabata put it to the test of science. Izumi and Kouichi are friends and collaborated on other research as well.

"Tabata" ("Irisawa"?) intervals do not include bridges, core work, or throwing medicine balls. In fact, it is biologically impossible to do Tabata's with core work or other smaller muscle groups. Why? Because the essence of the 20 sec on 10 sec off protocol is to challenge the cardiorespiratory system sufficiently to drive VO2 max (total body oxygen use) during the work phase. The core muscles are simply too small to drive VO2 to the level that skating, cycling, or running can as the legs muscle mass is huge by comparison. You can do 20/10's with circuit training, but it wont be "Tabata's", it will simply be intense circuit training.

Is this what Tabata's were designed to do (be part of base training)? Nope. Were these intensive intervals meant for postpartum exercise? Now way in hell. Did the woman in the Globe and Mail article do actual "Tabata" intervals or even close? No chance.

She most likely did intervals at a high intensity 20 on 10 off, but be sure.. she did not achieve the same biological state of intensity that the study participants did with Tabata back in early 1990's.

Also, the hormone relaxin is elevated during pregnancy which increases ligament laxity which allows for an easier birth (is "easier birth" an oxymoron?). Relaxin may be back to pre-pregnancy levels within a week or so after giving birth, but ligament laxity needs a few months to return to normal or close to normal, and progressively more challenging exercise that matches the bodies condition ought to be part of addressing this. Intensive intervals is not part of the recommendation.

It is simply wretchedly dishonest and misleading to attach the scientific merits of Izumi Tabata's research to some goof balls whack job phony fat loss program, boot camp program, or any interval program that isn't closely related to the original protocol and purpose. Do these trainers test your VO2 max? Do they monitor your power output stability and watch for the fatigue cut off described in the Tabata study? No and no. Rather they push you hard and when you slow down they push you more.. the exact opposite of what the study called for.

Just what exactly are Tabata intervals anyway?

10 minute warm up at 50% of VO2 max followed by 20 seconds at 170% of VO2 max power followed by 10 seconds of complete rest. The 20 on 10 off is repeated 7 to 8 times.

This is done 5 days per week, with the 5th day completing 30 minutes at 70% of VO2 max followed by a shortened set of the 20/10's (4 intervals instead of 7 to 8).

If they became too fatigued the interval was stopped. You have to go through specific testing to discover what your VO2 power is; without knowing this you will not be able set the correct pace for the intervals that are designed to achieve the published results.

If you're not a trained athlete or least a seriously hard core fitness enthusiast, it is unlikely that you'll be able to produce the effort required to complete Tabata's and you'll fatigue before completing the set.

Sound complicated? It is. This isn't simple intervals for quick fat loss (which doesn't exist anyway).

In order to get the published results of 23% in anaerobic capacity and approximate 13% increase in VO2 max, you have to do the protocol for 6 weeks, pretty much exactly as was done in the study.

How do I know all this? Because I read the damn study! A lot can be learned by reading the abstract, but to get to the details you have to read the whole study. And no, amending the intensity and specific exercises dramatically but staying with the 20/10's does not give you a piece of the same benefit, although pundits may play on this simple Simon intuition to sell you that very idea.

Can you get some benefit with 20/10's done any which way? Maybe, but doing so is virtually meaningless without measuring what you are doing, and is totally senseless if done too hard too soon.

How do I know how many calories Tabata’s burn off? Unlike the pedestrian nano-brained punk rip off artists (let me tell you how I really feel :-) ) that put themselves on a pedestal of guruness, I actually measure what I do with precise instruments, and so do other coaches and trainers who are not on the dark side.

Tabata intervals done on bike. About 84 calories burned.

The measurement shows 80kj (kilojoules) which is 336 Kilocalories (Calories). The human body has about a 18-25% efficiency converting food energy into mechanical work: 336X0.25=84

For more info on energy in food and human work (exercise) read this Wikipedia

Tabata's are extremely intense. I've prescribed them to athletes I train and done them myself; believe me when done correctly they are beyond extreme.

The truth is the majority of the population can't do Tabata's because they're not fit enough. But that doesn’t matter because for weight loss you don’t have to push through pain to be successful. You can lose fat with simple walking and dropping your food portion sizes appropriately.

Non-athletes can't do athlete training. It's impossible. You have to build yourself up the same way an athlete does.

For the rest of us we can only do that portion of an athlete program that is suited to our level of development, we simply don't have the horsepower or oxygen efficiency to do more. For many wanna be's that's a sad fact, for everyone else it's simply the way it is.

Want to lose fat? I have other posts on the subject and my website is full of detailed articles on how do so the right way, which takes personal commitment to change. D'oh! two C words in a row.

Glad I could get this off my chest. I've been lamenting the hype on Tabata's for a few years now and this Globe and Mail article debacle was what pushed me over the edge.

2 comments:

  1. Hahaha I like how much you toned down your language when you posted your comments on the globe article webpage. I couldnt agree with you more, but hey, a quick (albeit ridiculous) fix that results in supposed weight loss is going to have a lot more supporters than those who actually take the time to read through a research article. What surprises me the most is the woman who implements this training program, she`s a kinesiologist with her CPT. Shame on her!

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  2. Thanks.. I save the more opinionated stuff for my sites and try to be a little more ambassador like if I post somewhere else :-)

    I liked your comments on the Globe site.

    I like your comment on being surprised she's a kinesiologist. I'm finding this occurring more and more amongst certified and degree holding trainers- promoting the same bunk that used to be the domain of the back gym hackers.

    A degree or certification is no longer an indication of integrity or competency it seems.

    You're right.. quick fix claims get attention. That's what demagoguery is all about.

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