The Science of Slim: Exercise For Only 20 Minutes a Week?

Jonathan Bailor, author of "The Smarter Science of Slim"

Author Jonathan Bailor makes a bold statement: that you only need 20 minutes of exercise per week to boost metabolism and burn fat. Yep, just 20 minutes, nothing more ... and guess what? The science appears to support this. His book "The Smarter Science of Slim" (affiliate link) covers over 1,000 studies in an attempt to break down the real facts behind living well through proper nutrition, but also through exercise. I recently gave Bailor's book my strongest endorsement and considering I'm rather stingy with my endorsements, that's saying something.

The Program

Bailor suggests that you do an intense HIIT-style training on a Spin bike or by doing eccentric muscle stimulation to get to the deepest muscle fibers in your joints.  What this means is pedal intensely while standing up on a Spin bike for 30 second intervals, and do four or five total with recovery in between.  The bike should be set so it's hard to pedal and you're out of breath and can't do anymore by the end of the 30 seconds. For eccentric muscle stimulation, think of it as the "down." When you do a bicep curl, you contract the muscle by lifting the weight in your hand to your shoulder.  For eccentric, this would be the return of that weight.  Bailor actually only stipulates four moves as being necessary: a leg press, a seated row, a chest press, and an overhead shoulder press (he has four complimentary at-home moves, too). Doing this training will kick the body's metabolism up a notch because you're placing such a high demand on it.  The result is increased muscle, fat loss, and more energy.  The science backs this all up. BUT ... I know what you're thinking: what about cardio, regular weight training, all the other stuff we're supposed to be doing? According to Bailor, an active lifestyle will keep you fit, healthy, and limber, but over-training can actually backfire so that you gain more weight.  For instance, if you do a lot of cardio, your body will "eat" calorie-hogging muscle first and preserve it's fat stores because it thinks it's in starvation mode.  You will actually slow your metabolism down as your body tries to conserve energy because you're placing greater demands on it.
Let me say that again: over-exercising forces your body to conserve fat and breakdown muscle, the exact opposite of what you want.

An Active Lifestyle

Bailor does say (in one paragraph) that 20 minutes should not be all the activity you do each week.  He is actually an advocate of 10,000 steps a day and he strongly urges you to keep moving and doing activities that you enjoy.  So if you like to run, keep running, but don't think that training for a marathon will help you lose weight (it won't).  If you like to take a Zumba class for the energy, then by all means keep attending, but going six times per week is overkill and could very well leave you up a dress size, not down. His mantra is "smarter science," using what we know (via over 1,000 studies) to maximize our bodies' metabolism.  A healthy metabolism means you'll be lean, energetic, and strong.  I think it's safe to say we all want that. What do you think?  Are you skeptical of only 20 minutes per week?  Would you try it?  Do you think heavy bouts of cardio and/or weight training has helped you in the past? Cheers, Lisa Here's a collection of all my "Smarter Science of Slim" posts

About Lisa Johnson

Lisa Johnson here. I've been a personal trainer since 1997, a Pilates instructor since 1998 and the owner of Modern Pilates since 1999. I'm hoping to give you some good ideas to get or stay in shape with a healthy dose of humor and reality. Thanks for joining me.

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10 Responses to The Science of Slim: Exercise For Only 20 Minutes a Week?

  1. Jeremy Logsdon January 17, 2012 at 9:32 am #

    I am skeptical but also intrigued, especially since it doesn’t seem like he’s saying 20 per week as a “get out of exercise/activity free” card. This has definitely made me intrigued to check out his book!

  2. Lisa Johnson January 17, 2012 at 11:18 am #

    Thanks Jeremy, yes, he’s not saying you ONLY need to exercise for 20 minutes per week. He’s saying that’s the minimum you need to boost metabolism, but it has to be done in this specific way. :)

  3. Dean Ouellette January 17, 2012 at 11:26 am #

    Jeremy I was skeptical too. But I am just finishing up the book now, it is an amazing book. I have read roughly 10-12 health/diet books over the past year as I have become fascinated with the subject. This book may be the best of the bunch. The best parts are how easy he makes it to comprehend everything he is talking about and also how well documented with actual studies it is. The footnotes are quite extensive. Great book and great reviews Lisa. Thanks for sharing.

    PS. if you have questions about some of the things in the book as I did, if you tweet him at @jonathanbailor he has been great at answering the questions within a day or so.

  4. Sonia Simone January 17, 2012 at 1:21 pm #

    I did both workouts and have been surprised — neither one felt when I was doing it like it was some kind of life-changing exertion. (I already do heavy weight work and I already do intense cardio intervals — Bailor’s workouts are just shorter, more intense versions.) The part that surprises me is how thoroughly exhausted my muscles feel after the workout. Not sore, but *spent*.

    Also, after I did the cardio one, I was a lot faster in my treadmill intervals later in the week. I thought that was interesting.

  5. Jonathan Bailor January 17, 2012 at 11:06 pm #

    Hi Sonia – You are exactly right that if you already do heavy weight work and intense cardio intervals, The Smarter Science of Slim presents more intense (and therefore shorter) variations. The good news is that results are not linear with effort. The effort required to exercise infrequently and eccentrically enables us to cross a hormonal threshold with is impossible via any quantity of lower quality exercise…and yield dramatic results.

    During your bike workout did you increase the resistance so high that pushing yourself as hard as you safely could, it was impossible to pedal for more than 10 seconds at a time? During the resistance training, did you use so much resistance during the eccentric portion of the exercise that it was physically impossible to lower the resistance for more than 10 seconds (and, of course, impossible to raise the resistance with the one limb used to lower the resistance)? I ask because the workout itself is not the cause of exertion…the exertion is a function of the resistance used. The workout is useful in that it provides a way to maximize resistance while also maximizing safety.

    I find that it’s often helpful to use a few workout to ease your way into this level of resistance/intensity…and that you’ll know you’ve reached it when it’s impossible to do the same workout more than once or twice per week.

    Hope that helps, and thank you for giving the research a whirl.

    – Jonathan Bailor

  6. Sonia Simone January 19, 2012 at 12:07 pm #

    The resistance workout I’ve got at the right level, I might tweak the pull-downs slightly but it’s pretty much there.

    The bicycle workout is trickier because the bikes at my gym pause (which cuts all the resistance) when you go below around 55 rpm, so I’m going to need to experiment to find the right level & speed.

  7. Joe February 1, 2012 at 6:21 pm #

    Book called “Body By Science” by A Research Based Program to Get the Results You Want in 12 Minutes a Week, by John Little and Doug McGuff, MD 12 minutes I know hard to belive check it out at Dr. McGuff is a proponent of high-intensity interval training using weights, which is purposed to achieve many of the same results as Peak 8 exercises using cardio equipment
    High-intensity exercise, which engage your fast-twitch muscle fibers, is required if you want an effective aerobic workout, and can cut your workout time from an hour on the treadmill down to 12-15 minutes
    Your fast-twitch fibers are largely glycolytic and store a lot of glucose. When these muscles are recruited, it creates the stimulus needed to grow muscle. At the same time, it enlarges the glucose storage reservoir in the muscle, which enhances your insulin sensitivity
    Long, slow, distance-type of exercise can actually cause your intermediate and fast-twitch fibers to begin to atrophy. Aside from losing muscle mass

  8. ross July 6, 2014 at 12:50 am #

    High resistance spin bike blew my knee out
    Thanks a lot NOT!

  9. Lisa Johnson July 13, 2014 at 1:15 pm #

    Hi Ross, thanks for coming back and sharing your experience. I wish I could comment in more depth, clearly the resistance was too high for your current conditioning but I wonder if you have the form right as well? I hope you recover quickly and it’s nothing more than a day or two of soreness. That is a good cautionary for people attempting the bike, start off slowly and work up to a good threshold and if it feels wrong stop!


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