つい先ほど(日本時間で本日昼の12時5分)、冒険家三浦雄一郎さんが80歳でのエベレスト登頂を見事達成し、最年長登頂記録を大幅に塗り替えたとのニュースがありました。
多少は山をやっている者として、80歳でエベレストに登頂することはもちろん、それ以前に登るという意思を持続させ体調を管理し研鑽を積み実行し成功にいたるまでの長い道のりがいかに大変なものかは、素人レベルの体験からでもそれなりに推察できるだけに、心底素晴らしい快挙だと感服する次第です。

さてこのビッグニュースにちなんで、現代人は何歳になっても運動した方が良いしすることのメリットがあるという、アメリカ高血圧学会での発表演題からの話題を紹介します。

70歳以上の高血圧患者(最高齢は93歳)2077人に体力テストを行い、耐容運動強度(メッツ)からみて、685人を低体力(4.5メッツ以下しか耐えられない)、786人が中等度(4.6~6.5メッツまで可能)、606人が高体力(6.5メッツ以上に耐えられる)と分類し、9年間観察した結果、低体力群にくらべ、中等度体力群の死亡リスクは15%、高体力群では37%低く、耐容運動強度が1メッツ増す毎に全死亡リスクが8%減少すると言う解析結果となった。この研究で登録された人の最高年齢がたまたま93歳だったということですから、93歳が上限ではないと思いますが、要するに同じ年齢で体力がある人とない人を比べれば体力がある方が長生きすると予想され、その違いは93歳になってもみられる、ということかと思います。

そして高齢者の体力の高低は、持って生まれた素質もあるでしょうがより多くは生活習慣とくに運動習慣に依存しているのでしょうから、何歳になっても体を動かした方がいいということですね。ただ90歳になってやる運動が、散歩よりもエベレストの方が良いということではなく、「体力に応じてややきついと感ずる運動」というのが、安全でかつ効果が期待できる大事な目安だと思います。


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Never Too Old to Get Moving: Aerobic Fitness Lowers Risk of Death, CV Events, in Elderly

Michael O'Riordan


May 17, 2013



San Francisco, California — The results of a large analysis show a reduction in mortality among elderly patients who maintained high levels of aerobic fitness, including benefits in individuals as old as aged 93 years.

"The point here is that it doesn't matter what age you are, you have to maintain a certain amount of fitness because the body goes into hibernation if it thinks it isn't needed anymore," senior investigator Dr Peter Kokkinos (VA Medical Center, Washington, DC) told heartwire . "We know this from broken limbs and from astronauts returning from space--if you don't use it, you're going to lose it."


If you don't use it, you're going to lose it. Dr Peter Kokkinos

Presenting the results here at the American Society of Hypertension (ASH) 2013 Scientific Sessions in San Francisco, CA, Kokkinos said that while age is associated with declines in muscle mass, strength, endurance, and aerobic fitness, older individuals respond well to exercise and exercise could play a role in preventing these age-related declines.

Given that hypertension increases in prevalence as adults age, the researchers, led by Dr Michael Doumas (VA Medical Center) examined the benefits of exercise in 2077 hypertensive men 70 years of age and older. All patients underwent routine exercise tolerance testing, and their peak workload was estimated in metabolic equivalents (METs). Of the participating men, 685 were classified as having low levels of aerobic fitness (METs ≤4.5), 786 had moderate levels of aerobic fitness (METs 4.6-6.5), and 606 had high levels of aerobic fitness (METs > 6.5).

For every 1-MET increase in exercise capacity, the risk of all-cause mortality was reduced by 8% (hazard ratio (HR) 0.92; p < 0.001). Overall, mortality was 15% lower among those with moderate levels of aerobic fitness (HR 0.85; p=0.024) and 37% lower among those with high levels of aerobic fitness (HR 0.63; p < 0.001) compared with the low-fitness group. Average follow-up in the study was nine years.

To heartwire , Kokkinos said that researchers are only now beginning to understand how the body's metabolism shuts down when it is no longer active. Computer work and nonmanual labor, which constitutes a large portion of the US workforce, means many individuals sit for long periods of time. As documented in a recent Women's Health Initiative (WHI) analysis, prolonged sitting has negative cardiometabolic effects, which are risk factors for diabetes and cardiovascular disease in their own right.

"The main message is that we need to be active," said Kokkinos. "The patients in this study were 70 to 93 years old. We don't have to do a lot to stay healthy, but we have to do something. You don't have to run a marathon--a brisk walk is all you need. As humans, we were designed to do work."