Gender and fat loss

[Magpie]

Sorry Ladies, but the following article is not good news for us girls!

The 'sprintervals' training Steve Boucher mentions at the end consists of doing 8 seconds of flat-out full-on effort, followed by 12 seconds of slow recovery time, and ideally doing this 8/12 cycle for 20 minutes.  "Sprintervals" is best done using an exercise bike or rowing machine as it allows more control - theoretically you could do it running, but safety becomes an issue - unless of course you have access to an area where you can safely run hell-bent-for-leather for 8 seconds etc repeatedly.  I have tried this on a bike and let me tell you it's really really tough.  That said, having heard Steve Boucher explain the following on radio recently, guess what I'm going to push myself to do again!!

If anyone is interested in more info on "Sprintervals" training, check out http://blogs.news.com.au/dailytelegraph/yoursay/index.php/dailytelegraph/comments/big_girls_blog_the_professor_is_coming_online/

Funny enough, I learned about SLD from the Daily Telegraph site when Anacara mentioned it there.  Thank-you again dear Anacara!!




Gender and fat loss
Last Update: Friday, August 31, 2007. 4:02pm AEST

By Professor Steve Boucher

Overview: There are many reported anecdotes of husbands and wives going on an exercise program together and the husband losing significantly more weight than the wife. But does research support the notion that men and women’s body fat responds to exercise differently? If so, are there gender-based mechanisms to explain why women are different from men? This is important to establish because if women have greater trouble losing fat they are likely to need female-specific fat loss programs.

Do women lose less fat after exercise compared to men?: There is surprisingly little research into this topic. However, some well controlled studies have shown that women do lose significantly less fat when engaging in exercise-based fat loss programs compared to males. For example, Donnelly et al. (2002) carried out a 16-month exercise intervention in overweight males and females aged 17-30 years. They found that the men lost on average 5.2 kg of weight compared to no decrease in the women. A small number of other studies have reported similar findings. Mechanisms underlying gender differences are complex and include the following: differences in body fat distribution, smaller energy expenditure of exercise, greater energy intake, fat oxidation patterns, and societal forces.

Gender differences in body fat distribution: Females have a gynoid whereas males typically have a android fat distribution. Thus, females have fat stores on their hips, legs, and upper arms, whereas males concentrate their fat around their abdomen. Fat content for men is about 12-24% and for women about 15-35%. Women need to store extra fat to help with pregnancy. Female fat stores are generally in smaller fat cells around the hips. In contrast, men have larger fat cells around their abdomen.

Energy expenditure of exercise and compensatory intake: There is some evidence to suggest that compared to men, women have a smaller energy expenditure to exercise. Because women typically have less muscle than men the energy used up in exercise is significantly less for women of the same weight. Also research has shown that some women tend to increase their energy intake (eat more) after exercise more so than men. Other research has shown that men generally put on weight through ignorance of basic nutrition, whereas women tend to put on weight more because they use food as a strategy to cope with life’s stressors. Cortisol is a major stress hormone and has been shown to induce the body to store rather than burn fat. So gender difference in cortisol levels may have an influence.

Fat oxidation patterns: It also appears that for the same amount of physical effort women burn less fat than men. Gender difference in fat utilization, however, is a controversial area. Other hormonal gender differences may involve thyroid. Low thyroid activity is a major impediment to fat loss and Australian women have more thyroid problems than men.

Summary: It seems that men can perform more vigorous exercise which may be more conducive in reducing abdominal fat. Women are disadvantaged by their smaller muscle mass and larger fat mass. Also women, generally, may possess greater problems with a sluggish thyroid gland. Recently, we have shown that women can lose significant amount of fat using intermittent sprinting exercise. Thus, the 8/12 second lifesprint protocol may be powerful enough to induce significant fat loss in women.



*for the reference mentioned above see:

Donnelly et al. (2003). Effects of a 16-month randomized controlled exercise trail on body weight and composition in young, overweight, men and women. Archives of Internal Medicine, 163, 1343- 1350.

[multimoe]

If anyone is interested in more info on "Sprintervals" training, check out http://blogs.news.com.au/dailytelegraph/yoursay/index.php/dailytelegraph/comments/big_girls_blog_the_professor_is_coming_online/
 Recently, we have shown that women can lose significant amount of fat using intermittent sprinting exercise. Thus, the 8/12 second lifesprint protocol may be powerful enough to induce significant fat loss in women.

                Magpie, thanks for this great info.  I couldn't access the "Sprintervals" training info from the
             blog for some reason.

                I guess the following from Dr. Weil's site refers to the same program:
http://www.drweil.com/drw/u/id/WBL02023#2 

Burning Fat Faster

Here’s a novel exercise strategy that seems to burn fat faster. Researchers at the University of New South Wales in Australia recruited 45 overweight women and assigned them to two exercise groups. The first group did 20 minute sessions on exercise bikes alternating eight seconds of sprinting with 12 seconds of exercising lightly. The second group exercised at a continuous pace for 40 minutes. Both groups cycled three times a week for 15 weeks. The end result was rather dramatic. The women who alternated between sprinting and light exercise lost three times as much fat as the women who rode their bikes at a regular pace. The researchers speculated that the intermittent sprinting yielded better results because it produces high levels of catecholamines, chemical compounds which allow more fat to be burned from under the skin and within muscles being exercised. This increases fat oxidation, which leads to greater weight loss, they said. Alternating sprinting with light exercise can be applied to swimming, walking and rowing, the researchers said. They presented their findings at recent meetings of Australia’s Heart Foundation and the American College of Sports Medicine.

    Sounds rather easy, doesn't it? (Well, not quite.)

[Magpie]

Good one Trina!  Yes that is exactly the study by Steve Boucher that I was referring to.  It's bloody hard BTW and you really have to build up to the 20 minutes. The idea is to get your heart rate up really high for the 8 seconds and then use the 12 to recover.  And yes the number of seconds in this pattern were found to produce the best results.

In a recent radio interview  Dr Boucher said that running using the 8/12 pattern was not recommended as it takes alot of focus and you really couldn't get your heart rate up high enough to get the full benefit.  But that said, if running is your thing, what the heck, give it a try. 

Have to say I tried this on my treadmill and that really didn't work well BUT I tried pumping my arms hard as I walked for the 8 seconds sprint bit and it got my heart rate up at least noticeably even if not quite high enough. 

Stationary bikes or rowing machines are evidently best, or those elliptical trainers will work for this too.

[shovelqueen]

Treadmills won't change speed fast enough for the 8/12 sec intervals.  Would work on the road or track, though, I think.  I might try it a bit next run.

[Magpie]

Shovelqueen, I didn't try speeding up the treadmill, just how I walked and moved on it.  Quicker shorter steps and pumped my arms like a demented woman possessed.  Looked like an idiot I'm sure but it did increase my heart rate, but according to Dr Boucher, probably not enough.  Still anything that adds to a workout might be worth throwing in occasionally.

[shovelqueen]

Magpie, I once walked an entire 42 km marathon that way - took me 5 hours 55 min.  A long time to be pumping arms, but the arms are the key to getting the legs moving faster.  Also, make sure that your steps don't reach out in front of your body.  For best forward momentum, you want your foot to touch down right under your body, then roll smoothly over it.  It'lll really speed up your walking. Think shorter steps and arms bent and pumping, but NOT with shoulders hunched.  A much more intense workout.

[flickad]

I've been alternating running with walking just as a means of building fitness (I'm moving towards becoming more of a runner, from being strictly a walker, since I've been finding running exhilerating and a great means of releasing both tension and endorphins). Nice to know that this is advisable in terms of maximising fat loss as well- I'd love to have more tone.

[principessa]

I've done some of this "sprinterval" type of training, using the flights of stairs in my apartment building.  The interval that work(ed) well for me was 60 second intense followed by 90 second moderate.  I would climb the stairs as fast as possible for 60 seconds -- which was really difficult, then march in place or walk down the stairs (depending on where on the 6 flights I was after the intense interval) for 90 seconds.

I have to say, it really pumps up the heart/lungs -- just to the point of pain -- I did this for about a month, then lost motivation.  Having read the thread, I think it's worth doing again.

[Magpie]

Principessa, I know what you mean about the motivation - hearing the radio segment has given me the incentive to do sprintervals again. 
BTW Dr Bouchers research showed that the 8 second on / 12 off timing was optimum for fat burning.  Something to do with the way the chemicals are released in response. And yes it is a surprisingly tough workout, but again, he says 20 minutes 3 to 4 time a week is enough, with a short warm up and cool down after.

I skipped the cool down when I tried it and just gulped down the nearest cold glass of water!!