Category Archives: exercise

Outliers, Regression and the Sports Illustrated Myth

By appear­ing on the cov­er of Sports Illus­trated, sports­men and women become jinxed and shortly there­after exper­i­ence bouts of bad luck, goes the Sports Illus­trated Cov­er Jinx myth.

‘Evidence’ of the myth comes in the form of many indi­vidu­als and teams who have died or, more com­monly, simply exper­i­enced bad luck in their chosen voca­tion shortly after appear­ing on the cov­er of the magazine.

The Wiki­pe­dia entry for the Sports Illus­trated Cov­er Jinx has a thor­ough list of some “not­able incid­ences” and also provides a con­cise, sci­entif­ic explan­a­tion of the phe­nomen­on:

The most com­mon explan­a­tion for the per­ceived effect is that ath­letes are gen­er­ally fea­tured on the cov­er after an out­lier per­form­ance; their future per­form­ance is likely to dis­play regres­sion toward the mean and be less impress­ive by com­par­is­on. This decline in per­form­ance would then be mis­per­ceived as being related to, or even pos­sibly caused by, the appear­ance on the magazine cov­er.

Related: The Mad­den NFL Curse.

via Ben Gol­dacre’s Bad Sci­ence

Sedentary Lifestyle? Exercise Isn’t Helping

A some­what sedent­ary life­style com­bined with reg­u­lar exer­cise is turn­ing us into what physiolo­gists are call­ing ‘act­ive couch potatoes’–and that exer­cise, no mat­ter how vigour­ous, does­n’t appear to be coun­ter­act­ing the neg­at­ive effects of that sedent­ary life­style.

In rats, this life­style was found to pro­duce “unhealthy cel­lu­lar changes in their muscles” and increase insulin res­ist­ance and fatty acid levels in their blood. In con­clu­sion: a mostly sedent­ary life­style is bad for us, regard­less of exer­cise habits.

[Stud­ies have shown] that, to no one’s sur­prise, the men who sat the most had the greatest risk of heart prob­lems. Men who spent more than 23 hours a week watch­ing TV and sit­ting in their cars (as pas­sen­gers or as drivers) had a 64 per­cent great­er chance of dying from heart dis­ease than those who sat for 11 hours a week or less. What was unex­pec­ted was that many of the men who sat long hours and developed heart prob­lems also exer­cised. Quite a few of them said they did so reg­u­larly and led act­ive life­styles. The men worked out, then sat in cars and in front of tele­vi­sions for hours, and their risk of heart dis­ease soared, des­pite the exer­cise. Their workouts did not coun­ter­act the ill effects of sit­ting. […]

Dec­ades ago, before the advent of com­puters, plasma TVs and Room­bas, people spent more time com­plet­ing ‘light-intens­ity activ­it­ies’ […] Nowadays, few of us accu­mu­late much light-intens­ity activ­ity. We’ve replaced those hours with sit­ting.

The physiolo­gic­al con­sequences are only slowly being untangled. […] Sci­ent­ists believe the changes are caused by a lack of mus­cu­lar con­trac­tions. If you sit for long hours, you exper­i­ence no ‘iso­met­ric con­trac­tion of the anti­grav­ity (pos­tur­al) muscles’. […] Your muscles, unused for hours at a time, change in subtle fash­ion, and as a res­ult, your risk for heart dis­ease, dia­betes and oth­er dis­eases can rise.

via Waxy

The Effectiveness of Social Support on Exercise Goals

Inform­ing our friends and fam­ily of our res­ol­u­tions in hope that the social sup­port will encour­age us is an effect­ive tactic–as long as these people ‘check-in’ on our pro­gress at semi-reg­u­lar inter­vals.

That’s the con­clu­sion from a study where three groups of people had their exer­cise goals tracked under one of three con­di­tions: a reg­u­lar phone call from an exer­cise instruct­or, a reg­u­lar auto­mated call from a machine, and a con­trol group receiv­ing no calls.

The res­ults showed that hav­ing to report your pro­gress toward a goal drastic­ally increases the amount of effort under­taken–espe­cially when it’s a human check­ing-in on your pro­gress.

The caller, wheth­er human or com­puter, asked the par­ti­cipants to recite the amount of exer­cise they per­formed dur­ing the past week. Par­ti­cipants were then con­grat­u­lated on any exer­cise per­formed, and asked how the level might be increased in the week ahead. When lapses occurred […] the goal was to impress upon par­ti­cipants the import­ance of resum­ing the workout as soon as pos­sible. All ques­tions were designed to encour­age rather than to scold.

After 12 months, par­ti­cipants receiv­ing calls from a live per­son were exer­cising, as a mean, about 178 minutes a week, above gov­ern­ment recom­mend­a­tions for 150 minutes a week. That rep­res­en­ted a 78% jump from about 100 minutes a week at the start of the study. Exer­cise levels for the group receiv­ing com­pu­ter­ized calls doubled to 157 minutes a week. A con­trol group of par­ti­cipants, who received no phone calls, exer­cised 118 minutes a week, up 28% from the study’s start. […]

Some stud­ies by oth­er research­ers have sug­ges­ted that after eight weeks of reg­u­lar exer­cising many people can settle into a long-term habit of work­ing out.

The art­icle also cites a study on how meet­ing in groups to dis­cuss exer­cising goals (group-coun­sel­ing) showed a quad­rupling of exer­cise levels after three months and an even great­er jump at nine months (long after the group-coun­sel­ing ses­sions ended in month three). By con­trast, “the exer­cise level of a con­trol group rose dur­ing the study peri­od but at nine months had returned to near-baseline levels”.

via Nudge

Nine Diet and Lifestyle Tips for Longevity

By study­ing the world’s Blue Zones–“com­munit­ies whose eld­ers live with vim and vig­or to record-set­ting age”–Dan Buettner and team dis­covered a set of com­mon beha­vi­our­al traits in their sub­jects.

In his TEDxTC talk Buettner dis­cusses what he dis­covered to be the myths of liv­ing longer and the nine com­mon diet and life­style habits of those who live to be act­ive at 100+:

  • Exer­cise Nat­ur­ally: They don’t con­sciously exer­cise – rather, daily phys­ic­al exer­cise was a nat­ur­al part of their lives (walk­ing, using stairs, cyc­ling for trans­port, etc.).
  • Down­shift: They live a simple life.
  • Have a Pur­pose: Know­ing and act­ing with pur­pose and hav­ing a high­er goal leads to around a sev­en year increase in life expect­ancy.
  • Mod­er­ate Alco­hol Intake: I’ve dis­cussed this at length before.
  • Plant-Based Diet: Not a veget­ari­an diet, but a largely plant-based one.
  • No Over­eat­ing: They avoid over­eat­ing, typ­ic­ally by using ‘nudges’.
  • Friends and Fam­ily First: They typ­ic­ally think of their close friends and fam­ily first.
  • Belong to a Faith-Based Com­munity: Belong­ing to a faith-based com­munity, and meet­ing on aver­age four times a month, can add four to four­teen years to one’s life. Does this exclude athe­ists? I don’t see why a human­ist com­munity that meets the same rules (meet­ing reg­u­larly) would be dif­fer­ent.
  • Belong to the Right ‘Tribe’: They sur­round them­selves with the ‘right’ people. By doing so they pre­vent get­ting bad habits through social net­work effects (also dis­cussed pre­vi­ously).

via Dav­id DiS­alvo

More on the Cognitive Benefits of Moderate Exercise

“There is over­whelm­ing evid­ence that exer­cise pro­duces large cog­nit­ive gains and helps fight demen­tia”, says the Har­vard Uni­ver­sity psy­cho­lo­gist John Ratey, author of the 2008 book on the sub­ject, Spark.

While Ratey pro­pounds the “very clear” link between exer­cise and men­tal acu­ity, say­ing that even mod­er­ate exer­cise pushes back cog­nit­ive decline by “any­where from 10 to 15 years”, the Nation­al Insti­tutes of Health are more cau­tious:

Look­ing at redu­cing the risk of “cog­nit­ive decline in older adults,” [the NIH] wrote: “Pre­lim­in­ary evid­ence sug­gests a bene­fi­cial asso­ci­ation of phys­ic­al activ­ity and a range of leis­ure activ­it­ies (e.g., club mem­ber­ship, reli­gious ser­vices, paint­ing, garden­ing) with the pre­ser­va­tion of cog­nit­ive func­tion.” A few small stud­ies showed that “increased phys­ic­al activ­ity may help main­tain or improve cog­nit­ive func­tion in nor­mal adults”.

I’ve writ­ten before about the extens­ive cog­nit­ive bene­fits of exer­cise, but as Noah Gray (via) says, “it nev­er hurts to rein­force the mes­sage”.