The Telegraph Misses the Point…

Posted By elissa on Feb 8, 2010 | 4 comments

Wow.  It’s been a while since I’ve read an article about exercise that was THIS carelessly written… From the Telegraph:

Millions of people ‘waste their time by jogging’

Millions of people who strive to keep fit by jogging, swimming or going to the gym are wasting their time, scientists said.

Researchers have discovered that the health benefits of aerobic exercise are determined by our genes – and can vary substantially between individuals.

Around 20 per cent of the population do not get any significant aerobic fitness benefit from regular exercise, according to an international study led by scientists at the University of London.

For these people, regular jogging and gym work will do little to ward off conditions like heart disease and diabetes which aerobic exercise is generally thought to resist.

Researchers say they would be better off abandoning their exercise regime and focusing on other ways of staying healthy – such as improving their diet or taking medication.

Whaaaa????  That isn’t what the researchers actually said! Here’s the actual paper…

Given that ~20% of subjects fail to improve aerobic capacity with intense endurance training, while ~30% do not enhance their insulin sensitivity (12) it is clear we must develope genotype tailored lifestyle interventions. The present data now enable us to test the efficacy of a molecular screen for exercise responses (8) so that, for example, low responders for VO2max can now be randomised to alternative interventions to establish if they are low responders for additional parameters such as changes in post-exercise insulin sensitivity. Such an application of our data is consistent with the idea of using personalized medicine (48) to tailor life-style modification and hence we feel we provide a significant new milestone for the field. For those humans with an impaired ability to improve or even maintain their aerobic capacity, with exercise therapy, we may need to promote alternative exercise intervention paradigms or offer more intensive pharmacological and dietary protocols to help compensate for their genomic profile.

Two points: 1) the people who fail to significantly improve their VO2max may NOT be the same people who are “low responders” for changes in post-exercise insulin sensitivity. Although the article implies that insulin sensitivity was determined in this study, in reality, the researchers were citing numbers from a related paper published in 2005. Thus, low responders in one area but not the other could conceivably still benefit from standard aerobic exercise. 2) By establishing a dichotomy between “their exercise regime” and diet/medication, the author of this article makes it sound as if low responders should abandon exercise altogether.  Timmons et al., however, make it clear that “alternative exercise intervention paradigms” may be part of the equation. In fact, some of the Timmons’  other work lends itself to this interpretation:

The low volume, high intensity training utilized in the current study significantly reduced both glucose AUC (-12%) and insulin AUC (-37%), with a sustained improved insulin action until at least day three after the last exercise session. This was achieved without changes in body weight, and with a weekly energy-‘cost’ of training of ~225 kcal during the first training week and ~275 kcal during the second training week. This very modest increase in calorie consumption is in stark contrast to the ~2000–3000 kcal·week^-1 consumed during a typical aerobic training program [25, 34]. This implies, but does not prove, that the mechanism underpinning the benefits we observed with HIT, may be distinct from those responsible for the more modest improvements in insulin action with classic time-consuming aerobic training.

In this study, high intensity training produced improvements in insulin sensitivity better than those of conventional aerobic training.  Thus, other exercise modes may be more efficacious for low responders… not NO exercise, as implied.

In sum, the author takes a typical, “contrarian” attitude (i.e., exercise isn’t all it’s cracked up to be) and puts words in the researchers mouths to do it. Even worse, he fails to acknowledge the possibility that there might be benefits to aerobic exercise that have nothing to do with either preventing heart disease or diabetes.  These include stress reduction, prevention of osteoporosis and/or fat loss/weight maintenance.  Heck, sometimes I’ll do short (20 – 30 min), moderate-intensity, steady-state cardio workout just as a pick-me-up: it’s energizing and helps lift the fog without being particularly strenuous. So, it’s premature to suggest that low responders would be better off “abandoning their exercise regime” – we don’t actually know this, yet.

Honestly, is it too much to ask that reporters properly convey the points they’re writing about, and not leave erroneous impressions?  Not enough people exercise as it is, and in the absence of that “personalized medicine” directing folks to more targeted interventions, we’re better off encouraging – not discouraging – as many people as possible to get moving.