The First 20 Minutes Personal Trainer E-Book

Gretchen Reynolds

• Herausgeber: Icon Books
• Kategorie: Ratgeber
• Sprache: Englisch

Seitenzahl: 77

Veröffentlichungsjahr: 2013

Beschreibung

Much of what we thought we knew about fitness is turning out to be wrong. You should always stretch before exercising? Wrong! Sit-ups are good for you? Wrong! In the ideal companion to her brilliant and bestselling The First 20 Minutes, Gretchen Reynolds identifies these common misconceptions and develops a health and fitness workout tailored to your own level of ability – and all based on the latest scientific discoveries. Whether you have 2 minutes to spare, 10 minutes or 20 minutes, this ebook special will give you invaluable tips for optimising your fitness plan. You will also find out how to exercise to benefit specific problem areas such as the shoulder, lower back and knees. And finally there are insider tips on hot topics such as when to eat before exercise, whether beetroot juice improves blood flow to the muscles, how running backwards can liven up your workout, and why unplugging your headset may help you enjoy exercise more.

Leseprobe

About the author

Gretchen Reynolds writes the popular Phys Ed column for the New York Times. She also contributes to a number of other periodicals in the United States, such as the New York Times Magazine, O: The Oprah Magazine, Men’s Journal and Popular Science. She has won a number of awards for her writing and reporting, including two nominations for the prestigious National Magazine Awards.

She is also the author of The First 20 Minutes: The surprising science of how we can exercise better, train smarter and live longer (Icon Books, 2012).

Also by Gretchen Reynolds:

The First 20 Minutes

This electronic edition published in the UK in 2013 by

Icon Books Ltd, Omnibus Business Centre,

39–41 North Road, London N7 9DP

email: [email protected]

www.iconbooks.net

Published by arrangement with Hudson Street Press, a member of

The Penguin Group (USA) Inc.

ISBN: 978-184831-644-7

Text copyright © 2013 Gretchen Reynolds

All rights reserved.

No part of this book may be reproduced in any form, or by any means, without prior permission in writing from the publisher.

Typeset by Marie Doherty

Publisher’s note:

Every effort has been made to ensure that the information contained in this book is complete and accurate. However, neither the publisher nor the author is engaged in rendering professional advice or services to the individual reader. The ideas, procedures and suggestions contained in this book are not intended as a substitute for consulting with a health professional. All matters regarding your health require medical supervision. Neither the author nor the publisher shall be liable or responsible for any loss or damage allegedly arising from any information or suggestion in this book.

Contents

About the author

By same author

Full title page

Copyright information

Half title page

Part I: Myth Information

Part II: Fitness That Fits Your Schedule

Part III: Why Resist?

Part IV: Your Next Move

I

MYTH INFORMATION

So much of what we thought we knew about fitness is turning out to be wrong. Here are 15 common misconceptions and what science now says. Best news: no sit-ups!

MYTH #1: You should always stretch before exercising

In 2010, researchers at Florida State University asked ten male athletes to stretch for 16 minutes, then had them run for an hour on a treadmill. In a later session, the same crew sat quietly for 16 minutes, and then hit the treadmill for the same duration. Without the pre-run stretch, the men covered significantly more distance while consuming less oxygen. The researchers’ blunt conclusion: ‘Stretching should be avoided before endurance events.’

Still, the pre-game ritual endures. Most of us were taught by our school PE teacher that you need a routine of static stretches – touching your toes and holding for 30 seconds – to be fast and flexible. Most physiologists now believe that when you elongate muscle cells, you cause a ‘neuromuscular inhibitory response,’ said Dr Malachy McHugh, the director of research for the Nicholas Institute of Sports Medicine and Athletic Trauma in New York and an expert on flexibility. By triggering a protective counter-response in the nervous system, which tightens the muscle to prevent it from overstretching, you render yourself less powerful. In experiments, static stretching typically decreases strength in the stretched muscle by as much as 30 per cent, an effect that can last for up to 30 minutes. That means basketball players who perform static stretches can’t leap as high, and sprinters can’t generate as much leg propulsion.

What’s more, stretching does not seem to prevent injuries. In several large-scale studies of both athletes and military recruits (who march and run for hours), static stretching did not reduce the incidence of common overuse injuries such as Achilles tendinopathy or knee pain.

NEW BOTTOM LINE: At best, you’re probably wasting your time with stretching before exercise.

Instead, before your next race or workout, throw in the following five-minute ‘ballistic stretching’ routine. Because they don’t stretch tissues to the point of activating the nervous system’s protective instincts, these exercises won’t cause the negative effects of your old-school toe touches.

Jumping jacks (20 or so)Skip, forwards and backwards (for about a minute)High-leg marches: Walk forward, kicking each leg up, knee straight, in front of you, like a tin soldier (for another minute or two)Kick your own butt: Hop on one leg, kicking the other leg backward, touching your buttocks (aim for about 10 repetitions with each leg)

MYTH #2: Running ruins your knees

Jog often and well-meaning friends and meddlesome strangers will warn that you are going to ruin your knees. What they mean is that running will cause cartilage degeneration and arthritis, leaving you with a limp and a large orthopaedist’s bill.

But science disagrees. A resonant 2011 review of the relevant research found that regular physical activity, especially running or playing sports, affected people’s knees negatively at first glance: active people had more bone spurs than the couch-bound, which would usually be considered an indication of knee dysfunction.

Yet those in the fit group also rarely suffered from joint-space narrowing, a condition that usually accompanies bone spurs; it occurs when your knee’s cushioning cartilage wears away and your bones begin closing in on one another, threatening to cause painful bone-on-bone arthritis.

In fact, in most of the studies that the scientists reviewed, active people had greater cartilage volume and were in less danger of developing arthritis than people who coddled their knees by not running or playing sports.

What the review’s findings show, said study co-author Dr Flavia Cicuttini, a professor at Monash University in Australia, is that knees adjust to the forces created during activity, in part, it seems, by sprouting adaptive bone spurs. Overall, Dr Cicuttini said, ‘physical activity is good for joints.’

That conclusion received real-world confirmation via a wonderful study from Stanford University that followed middle-aged runners for nearly 20 years, by which time they’d become elderly runners. In the beginning, a few had creaky, mildly arthritic knees. (Interestingly, none of an age-matched control group of healthy non-runners did.) But after 20 years, only a few of the runners had noticeable arthritic changes in their knees joints, while 32 per cent of the control group did, with 10 per cent of them having developed severe arthritis versus less than 2 per cent of the runners.

Similarly, a German study of middle-aged marathon runners found no deterioration within the racers’ knees over the course of a decade, leading the researchers to speculate that ‘continuous exercise may be protective, rather than destructive’ to knees, perhaps by stimulating cartilage cells to divide and rebuild the knees’ cushioning. By the end of the Stanford study, the runners, now in their 70s and 80s, may no longer have been fast (if they’d ever been). But their knees were largely intact and they were all still running.

There is a substantial caveat to this good news, though: vigorous physical activity, particularly running, seems to exacerbate damage if you have a past knee injury, such as a torn anterior cruciate ligament (ACL) or meniscus (the pillows of cartilage that cushion the thigh bone and shin bone) or if you regularly have pain or swelling in your knee, especially after exercise, which can be a symptom of early arthritis. ‘Activity on an already diseased joint is what is bad for the knee,’ Dr Cicuttini told me. By many estimates, more than half of all people who tear their ACL will develop arthritis in that knee within 10 or 15 years, a process that might be hurried by the repetitive motion of running.

To slow the onslaught, most experts advise those with a history of knee injury to avoid weight-bearing activities, like running, as well as sports that involve side-cutting and sudden stops, including basketball and soccer. Instead, you might want to consider sports such as cycling or swimming (but avoid breaststroke, which stresses knees). If you take up cycling, have your bike correctly fitted. A study published last year concluded that a 5 per cent difference in the height of a bike saddle could change the magnitude of forces applied to the knee by as much as 16 per cent. The maximum angle of your knee during the pedal stroke shouldn’t exceed 30 degrees, the study’s authors write.

NEW BOTTOM LINE: Healthy human knees are generally made healthier by running. If you currently run without knee pain, then it’s likely that you can continue without inducing arthritis. But talk to your doctor if you hear creaking, feel pain, and especially if you have a past history of knee injury, which can predispose your knee to instability and cartilage loss. And visit Part III, which details exercises designed to stabilise and protect the knee, advisable for anyone planning to still be using his or her original-equipment knee joint decades from now.

MYTH #3: There’s no such thing as too much exercise

When exercise scientists in England recently scanned the hearts of retired English Olympians and of members of the elite 100 Marathon Club (entry to which requires exactly what the name suggests) and compared the scans to those from a group of active but not competitive older men, they were startled to see that the serious athletes were far more likely to have scarring in their heart muscle than the merely active group.