November 10, 2022

Plyometric training boosts 5K time in already highly-fit runners

This running specific training experiment gets high marks for the quality of the subjects investigated. They were all capable of 5K times around 15:00. And there were a lot of them--60--for a trial of this kind.  

Here’s what happened. The all-male subjects were divided into four groups who, for 8 weeks, did pyramidal training, polarized training, or one of these with plyometrics added to the mix. Meanwhile, “training load was kept constant.” 

And the winner was? Basically, it was the plyometrics, which made both pyramidal and polarized training more effective. After the two month intervention, runners in the PYR+PLY group improved their 5K times by 2.4% and in POL+PYR by 2.1%. The researchers concluded: “Including plyometric training once a week appeared to be more efficacious in maximizing running performance.” More at Scandinavian J of Medicine & Science in Sports. 

Are we “Born To Run” on the forefoot/midfoot?

Or: The evolution of the runner’s foot strike. There are a lot of reasons to read Daniel Lieberman’s papers and books. He’s curious, engaging, and interested in both running and health. But mainly there’s this: He’s a scientist, not a didact with monovision. He follows the evidence. When the evidence changes, he acknowledges it, and modifies his view. 

This has happened in the case of his view on a natural running form. As you’ll remember from the “Born to Run” days--he co-wrote an influential journal paper that used that headline, but isn’t author of the best selling book with the same title--Lieberman believed that forefoot/midfoot running seemed to have an evolutionary basis. This meant that it was likely the best-healthiest way to run.  

When he did studies in Kenya’s Rift Valley and then with the Tarahumara runners in Mexico, he found confirmation for his hypothesis. He was strengthening his argument. But scientists don’t stop searching when they reach N = 2. So Lieberman kept looking at foot strike patterns in hunter-gatherer societies around the globe. 

And suddenly his theory started to unravel. The last three primitive peoples have proven to be heel strikers. In a new paper, Lieberman and colleagues filmed the Tsimane forager-horticulturalists of Bolivia. The Tsimane don’t run much at all; rather they are big walkers, usually logging 5 to 6 miles a day. Almost 90 percent report that they have been barefoot much of their lives. Yet when asked to run for the high-speed video camera, 99% ran with a heel strike, and 98% were over striders. Oops! 

So now the Lieberman hypothesis has itself evolved a bit. It sounds like this: Modern runners place their feet on the ground in different ways, and early runners likely did the same. If they came from cultures where running was important for subsistence, social practices, religion, etc, they probably came to learn efficient, forefoot-midfoot, shortish-stride running. If they came from cultures where running was not important, then they ran as they walked--with a heel-first stride. More at Evolutionary Human Sciences. 

Small temp differences have a big effect on marathon finish times

Sunday afternoon in New York City, I sat on the finish-line grandstands for about an hour as many midpack runners were churning, sprinting and sometimes walking the final 50 yards. Most looked pretty good--not like a mid-summer sweatathon--although more than usual seemed to be suffering from leg cramps.  

No question, it was unseasonably warm and humid in NYC all weekend. Great for tourists and spectators, but suboptimal for race times. MarathonGuide.com reported that the average finish time of 4:50 was about 13-14 minutes slower than in other recent years.  

Chinese researchers recently checked out the performances of 610 runners who completed 3 straight versions of the Singapore Marathon. And, yes, a couple of degrees of temperature difference (plus humidity) had a significant effect on their finish times. When the wet bulb temperature (incorporating the dry bulb temperature and the humidity) rose by 1.5 degrees C, times slowed by more than 9 minutes for both men and women.  

The study also uncovered a bit of marathon-weather cruelty, and one modest tip. Cruel: Bad weather is likely to hinder your performance more than improved training could boost it. Tip: On warm days, don’t run with a pace team or other group. Get away from the group heat pump, and put yourself in position for maximum air circulation. More at Temperature. 

How to train like a 9-time NYC Marathon winner

Well, you could simply run 100 to 120 miles a week. That’s what many bigtime marathon runners do and have done for 5 decades now. Or you could mimic the training of Grete Waitz, who won 9 times at NYC in addition to a World Championships victory, several London Marathon titles, and a silver-medal behind Joan Samuelson in the 1984 Olympic Marathon. 

Waitz died from cancer at a youthful 57 in 2011, and her training logs were analyzed several years later. The resulting journal paper found that she ‘trained far below the volume reported for the current world record holder [then Paula Radcliffe, 2:15:25].” Waitz normally ran about 70 to 80 miles a week, with many runs of 7 to 8 miles at 5:30 to 6:00 per mile--very close to her marathon pace. She didn’t do many long intervals, but hit the track for a hard, short interval workout once a week.  

Today, everyone seems to aim for an 80/20 easy/hard training distribution. Waitz trained with about a 50/50 distribution. And it worked. More at Int J of Sports Science & Coaching.  

For time-efficient workouts, try a few hard bike intervals

Sometimes you just don’t have time to log the run you were planning. Or maybe you’ve been feeling a niggle or two, and want to make sure they don’t turn into full-setback injuries. In these cases, a few short “sprints” on an exercise bicycle could help preserve your fitness. 

Researchers used the following protocol with highly fit NCAA middle distance runners. For 4 weeks, they asked the runners to drop several of their typical 4 to 6 mile runs. Instead, on those days, the runners performed 4 nearly-all-out, high-resistance 20 second intervals on an exercise bicycle. They took long recoveries--4 minutes--before and after the intervals.  

Pre- and post-protocol testing showed no difference in subject vo2 max. The investigators interpreted this in a positive light, especially since there were no changes in stride frequency and length despite much less time spent with run training “The study shows how training could be modified to be more time-efficient,” they concluded. It’s also possible, though not studied here, that some interval training can be done on a bicycle rather than with full body weight, thus reducing likelihood of injury. More at Sports Medicine. 

Elliptical training can also promote great running fitness

There are a variety of elliptical machines out there, some of which mimic your running stride more than others. Many offer a potentially valuable form of cross-training and injury-protection for runners, as the below linked article explains at length.  

One of the case studies turned a lot of heads a year ago, including mine. After finishing second in the NCAA Cross-Country Championships, Univ of Florida runner Parker Valby (female) explained that she had only been doing two run sessions per week. Everything else was either an elliptical workout or pool running. Valby will be a co-favorite in this year’s Championships in little more than a week. More at Trail Runner. 

An alternative view on salt during long exercise races

Several weeks ago I noted a randomized, crossed-over trial from the European J of Applied Physiology that supported the use of sports drinks with more sodium to assist “long lasting, moderate intensity exercise in the heat.” However, that’s not a universal finding. Here’s a report on another recent paper that mathematically estimated “sodium requirements of athletes across a variety of exercise scenarios.” The author concluded that “Replacing sodium was unnecessary in all realistic scenarios” in an elite marathon. However, it did become important in a 100-mile ultra. More at Outside Online. 

Unexpected: Strength exercise beats aerobic for migraine

I count myself lucky that I’ve never suffered from migraine headaches, which strike 3 to 4 times more women than men. But I would have guessed that gentle, moderate exercise was the smart path forward. Nope. Quite the opposite, which I think will surprise many others also.  

Here’s the conclusion of a systematic review and meta-analysis of studies looking into exercise and migraine headaches: “Strength training exercise regimens demonstrated the highest efficacy in reducing migraine burden, followed by high-intensity aerobic exercise.” 

So you apparently get more relief from grunting and pushing hard. This goes into my ever-expanding bucket of “exercise paradoxes.” I’ll have to flesh them out some day. More at J of Headache Pain. 

Have an “activity snack” every 30 minutes

We’ve known for a while now that prolonged sitting is bad for our health. Even if you’ve done a solid 30 to 60-minute workout sometime during the day, many-hours of sitting can wipe out some of the exercise benefit. The American Diabetes Association and others recommend that we at least stand up every 30 minutes or so to improve glucose levels. 

But simply standing up doesn’t engage much muscle, burn many calories, or affect your physiology. To do that, you’ve got to move more. For instance, you could take a brisk 2-minute stroll, or do 15 chair-squats right in your office or from your favorite TV chair. 

In fact, exercise physiologists are now recommending that we do this all day long--and you get a few bonus points if you follow the recommendation in the hour or two after a meal. And they’ve got a catchy new name for such regular, short-duration exercise--”activity snacks.” You shouldn’t be snacking on junk food, but you should definitely include activity snacks in your total-health routine. 

Why? Because 2 minutes of solid movement is enough to increase “amino acid utilization for myofibrillar protein synthesis.” In other words, it stimulates your muscles enough to improve insulin sensitivity and boost strength. More at J of Applied Physiology

SHORT STUFF you won’t want to miss

>>> Late afternoon and evening exercise protect against diabetes. >>> Little evidence for calcium and Vitamin D for bone health in middle-age and beyond

>>> RCT: Pollock protein beats whey protein for strength-muscle in older women. 

GREAT QUOTES make great training partners

“In running, it doesn't matter whether you come in first, in the middle of the pack, or last. You can say, 'I have finished.' There is a lot of satisfaction in that.”

--Fred Lebow, founding race director of the NYC Marathon