Paleo Runners

Tuesday, September 6, 2011

Good Running Form Video

A Case Against Cardio (from a former mileage king)

(Article by Mark Sisson, marksdailyapple.com) We all know that we need to exercise to be healthy.

Unfortunately, the popular wisdom of the past 40 years – that we would all be better off doing 45 minutes to an hour a day of intense aerobic activity – has created a generation of overtrained, underfit, immune-compromised exerholics. Hate to say it, but we weren’t meant to aerobicize at the chronic and sustained high intensities that so many people choose to do these days. The results are almost always unimpressive. Ever wonder why years of “Spin” classes, endless treadmill sessions and interminable hours on the “elliptical” have done nothing much to shed those extra pounds and really tone the butt?

Humans, like all mammals, evolved two primary energy systems that powered the skeletal muscles of our hunter-gatherer ancestors 40,000 years ago and that would keep us all well-powered the same way today, if we weren’t so bent on circumventing them with our ill-fated (literally) lifestyle choices.

The first energy system relied heavily on the slow burning of fats, keeping us fueled while we were at rest or sleeping, yet also allowing for continuous or intermittent low levels of aerobic activity (think of our ancestors walking across the savannah for hours foraging for roots, shoots, berries, grubs, insects and the occasional small animal). It makes sense. Fats are very efficient fuels that are stored easily in the fat cells and burn easily and cleanly when lots of oxygen is present (as when we are breathing normally). Even if there’s no food in the immediate area, a well-trained fat-burning hunter-gatherer could continue walking and foraging for days without compromising his or her health or efficiency.

The second major energy system we developed through evolution was an ATP-fueled system that allowed for intense loads of work to be done in very brief bursts (think of our hunter-gatherer ancestors sprinting to the safety of a tree to avoid being eaten by a lion). ATP is always sitting right there within the muscle cells, available in a split second, and it is the highest octane fuel we have. In fact, it’s ATP and adrenaline that allow the little old lady to lift the front end of the Ford Fairlane off her husband when the jack fails. Unfortunately, the muscles can only store about 20 seconds worth of this precious fuel to complete life-or-death tasks. If our ancestors survived that quick sprint to safety, their ATP reserves were filled again within minutes using the other energy systems. The rest is HERE

Monday, September 5, 2011

Why Do I Do It (...because I can)

What a weekend, and why do I do it? As a 41 year old that's been on-again/off-again into fitness, I find myself in an upswing in concern for my performance. From 2009-end of 2010 I checked off so many goals I had set up for myself, first 1/2 and full marathon, first 50km, 50miler, etc. But since I don't have years and years of mileage and good running form under my belt, I always seem to suffer some pulled muscle or inability to tolerate some trail missteps. This brought me back to strength training. My honey-bunny encouraged me to try out her crossfit gym and I am glad she did. Today was an indicator of how far I have come. 9mos ago when I finished my foundations class I ended it with a 7round 1/2 Cindi, today I did 10rounds+22. This is a way to quantify the differences in my strength and performance in other areas. November 20th is my 'true test' of this added fitness. The JFK50 second try!! Last year it took me 10+1/2 hours to complete that race. I went out so strong and hurt myself by mile 15'ish. I was even sitting on the ground contemplating DNF'ing. This year I know I will have the strength, my cardio capacity is huge, my running form has improved. Of course a long race such as this will have plenty of curve balls, but all I can say is 'bring it'!

Saturday, September 3, 2011

The Effect of Running Shoes on Lower Extremity Joint Torques

Objective

To determine the effect of modern-day running shoes on lower extremity joint torques during running.

Design

Two-condition experimental comparison.

Setting

A 3-dimensional motion analysis laboratory.

Participants

A total of 68 healthy young adult runners (37 women) who typically run in running shoes.

Methods

All subjects ran barefoot and in the same type of stability running footwear at a controlled running speed. Three-dimensional motion capture data were collected in synchrony with ground reaction force data from an instrumented treadmill for each of the 2 conditions.

Main Outcome Measurements

Peak 3-dimensional external joint torques at the hip, knee, and ankle as calculated through a full inverse dynamic model.

Results

Increased joint torques at the hip, knee, and ankle were observed with running shoes compared with running barefoot. Disproportionately large increases were observed in the hip internal rotation torque and in the knee flexion and knee varus torques. An average 54% increase in the hip internal rotation torque, a 36% increase in knee flexion torque, and a 38% increase in knee varus torque were measured when running in running shoes compared with barefoot.

Conclusions

The findings at the knee suggest relatively greater pressures at anatomical sites that are typically more prone to knee osteoarthritis, the medial and patellofemoral compartments. It is important to note the limitations of these findings and of current 3-dimensional gait analysis in general, that only resultant joint torques were assessed. It is unknown to what extent actual joint contact forces could be affected by compliance that a shoe might provide, a potentially valuable design characteristic that may offset the observed increases in joint torques.

Entire Study Here