ATC 312: How 4-Second Sprints Can Transform Health (And Prevent You From Sitting For Too Long), Getting Back To Exercise as PLAY, Building a Smart Weekly Schedule, and More

June 5, 2020


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Intro Discussion:

Covid & Movement via Garmin

Article from Garmin about health trends since COVID

  • Steps decreased 12% in April
  • But workout activity steps increase 24%
  • People exercising more to offset less movement?
  • Epidemiological studies indicate that most American adults sit for a least 10 hours a day 
    • Prolonged sitting leads to increased risks for heart disease, Type 2 diabetes and other metabolic disruptions, high circulating TGs (muscles at rest don’t as easily break up TGs).
    • Athletes are not immune to this: Even an hour-long workout may not be enough to combat prolonged sitting. (Your body still might have difficulty with fat metabolism the next day.)
  • More people are building out home gyms.
    • In addition to doing a complete workout in your home gym, consider trying “slow weights.”

4-s Sprint Study

Hourly 4-s Sprints Prevent Impairment of Postprandial Fat Metabolism from Inactivity

  • Interrupting a long day of sitting with just 5 x 4 sec sprints every hour for 8hr (in this case cycling) can have the following benefits NEXT DAY:
    • Reduce postprandial plasma lipids by 31% 
    • Increase fat oxidation by 43%
  • Glucose/insulin unchanged in this study
    • However, I’ve noticed that sprints in the 1-2hr window post-meal can lower PP glucose for those who need that as an intervention. 
  • Add that up and it’s less than 3min a day of sprinting, not including recovery interval between sprints. (They had a 45sec rest between each set of 5.)

Suzanne S. asks:

How to build a smart weekly schedule?

Hey guys!

I’m a long time listener and really value the advice you two hand out.  You keep me company early on Saturday mornings!  I liked your May 8th podcast which discussed training for life vs a race and it sparked a question.  I’m guessing that I might be overthinking, the way I often do, but here it is anyways:

Brief history: I’m a 39 yr old female who loves exercise and getting outdoors first thing in the morning.  I used to run half marathons (middle of the pack, trained with a running group) but I burnt myself out 5 years ago due to too much exercise and work and stress and not enough rest and relaxation.  I started following the MAF approach and have learned a lot about listening to my body.  I also have never really gotten to the point that I can do anything more than a shuffle at MAF.  My routine for a few years has been a 45 minute shuffle/walk (5ish times/week) around the flattest streets that I can find in my neighborhood.  It gives me a dose of fresh air but otherwise it feels lame (because it’s neither a walk nor a run) and I end up not having time in my day for other exercise.

I should mention that my goals are to be healthy, strong and well-rounded and be able to comfortably go for an easy run with a friend once in a while.  I’m not interested in training for a race or running long distances.  I also have to be careful about stress and not letting myself overdo it in terms of exercise.

During this weird covid time, I’ve switched things up a bit and have been going on some shorter non-MAF runs (25-30 min, heart rate around 160 at an easy pace – feels good as long as I keep it short), lots of walks and doing more strength work (body weight exercises, TRX and some weights at home, nothing crazy heavy).  I get a nice little boost of energy from these workouts.  I like the variety and although I have this bad feeling psychologically about letting my heart rate go up, I am having way more fun!  My question is as to how to schedule things: I’ve heard of the idea of making hard days hard and easy days easy.  Would it make more sense to do strength work on the same days as my short runs and then have a few days/week where I stick to things like walking and yoga?  Or is it ok to do a little bit of hard work every day as long as it’s for a short time – say a 25 min run followed by a 20 min walk a few days/week and a 25 min strength session on the alternating days with one rest day/week…

Again, maybe I’m overthinking but would love to hear what you have to say. Thanks again for all you do and take care during these crazy times!

What the Coaches say:

  • Burnout is descriptive of a mental condition, not a physical one. Lucho doesn’t see any indication of physical overtraining in your language.
  • Your efforts to mitigate stress are actually causing you more stress!
  • Put your HR monitor away for a month. Allow yourself to have guilt-free freedom of choice to exercise the way you like. Be honest with yourself about perceived exertion, and do what feels good physically and mentally.
  • With no races planned, there is no correct training.
  • Your training at 160 bpm is almost certainly still aerobic.
  • Take a more playful approach to your training. Try to release some of your rigidity.
  • The intensity of your runs doesn’t seem particularly difficult for you. Plus, the 25 min strength workouts also don’t seem too strenuous. Feel free to experiment. Try a week of running 5 days with 2 of those runs at 160 bpm and strength/walks as you see fit. See how you feel.
  • When work is stressful, don’t add the extra stress of a hard workout.

Alyssa asks:

MAF feels too hard, body feeling run down

Hi Endurance Planet Team!
I’m a new listener and am so glad I found the podcast! I’ve been listening pretty religiously and super grateful for all the information you put out!
I learned about MAF through the show and have started trying to incorporate it in my runs but have found that my comfortable running pace has kept my heart rate well under my MAF goal. I’m wondering if this might be a strength or muscle power issue? Would you recommend running fast enough to reach my MAF range even if it means I will burn out and need to run shorter distances?
For some context, I just got back into running over the past two months while the stay at home order has been in place. I mountaineer/alpine ski and have a strong aerobic base and lots of weekly miles in my training already, although very little of them while running. I also currently (and historically) incorporate low intensity strength training in my routine 4-5 times per week, focusing mainly on physical therapy style workouts and usually 2 sessions a week focusing solely on legs. I’ve had a meniscus tear, BAD ankle sprain, and Achilles injury within the past six years but over the past two years have stayed injury free by really dialing in mobility and strength training especially for my legs.
I’m 28 and per the standard MAF formula (180-28) my target is 142-152. To get myself up to the 150-152 range I need to be running up a steep hill for a few minutes or running close to a sprint and there’s no way right now I’m strong enough to keep that pace for a run. For example, I did a 13 mile run yesterday on mostly flat trail and road (~1000’ gain total) and my heart rate pretty much stayed around 130-132 bpm the entire time. Even when I do shorter 5 mile runs, for example, my natural pace keeps my heart rate at about 130 bpm.
I think I could definitely push myself to run faster and get my HR closer to my MAF range but would have to cut back on my weekly volume. I’m running between 20-25 miles per week right and would like to slowly increase that base (I’ve been adding ~1-2 miles per week). I don’t have any races in mind but I’ve been loving trail running so much and would be stoked to one day incorporate it into my mountaineering goals. Being able to run and climb some mountains light and fast vs. hauling a bunch of over night gear for a climb is an exciting prospect to me. And just running at higher altitudes and more remote places in the wilderness is a super exciting prospect for me too. So frankly, I really don’t care about going fast I care about going far and having the endurance to get a lot of miles and elevation gain in. And my primary goal is also metabolic health and remaining injury free.
Just curious how you think I should be using the MAF method in my weekly training given my goals and where my comfortable pace is keeping my HR at?
My pace on flatish road at my MAF HR is ~8:15-8:30 min/miles. My pace at ~132 HR is ~10:00 min/miles. I have only done one MAF test on a rolling/mildly hilly trail with the following times per mile:
1. 8:16
2. 8:28
3. 8:21
4. 8:35
5. 8:47
I’m also wondering if I can add another question? 🙂 I’m wondering what your opinion is on if it’s possible for me to continue running at MAF (or even just my perceived easy pace closer to 10 min/miles) while trying to balance out my hormones?
I recently got bloodwork and had high SBGH, testosterone, and estrone. My estrogen was in the normal range. I sadly didn’t get my cortisol tested but I just know it’s high. I struggle with waking up in the middle of the night between 1-3 AM with a stressed and sometimes ravenous feeling. This is especially common after long weekends spent climbing/mountaineering. I’m grateful my job, relationships, and daily life are not stressful to me but I’m very type A and have always struggled with letting myself relax so I tend to operate in a more tense state anyways throughout the day to try to get as much done as possible even when I don’t need to. So I’m thinking I need to find a better balance with how I operate daily and how I handle my training to lower my cortisol and get my other hormones in check. I feel super good about my diet but do just feel like my body is out of whack for the past several years. I don’t really have extended periods of rest because I’m able to climb, ski, etc year round. I do try to get one-two rest days per week but I usually still do core and mobility work :/ I know I need to find a better balance I’m just trying to figure out how much to pare back and if I might need to take a break from any form of cardio altogether for awhile to let my hormones rebalance? Or if low intensity biking, running, hiking, and rock climbing could be okay for me and maybe take a month or so off from more intense forms of cardio like hiking/climbing with a heavy pack on all day and see if that helps?

What the Coaches say:

  • Lucho thinks the MAF formula is wrong for you. What’s the highest HR number you’ve ever seen? That’s indicative, a little bit, of where your natural HR capacity is.
  • 125-135 seems to be where you should be training.
  • Struggling at your MAF HR is probably indicative of your overall state of health.
  • If hormones are out of whack, you might consider looking into symptoms of PCOS.
  • Do some at-home blood glucose testing. See if your fasting is above 90 (not ideal) or 100 (problematic) and postparandial levels are higher than 140 after an hour.
  • Lucho doesn’t think this is a strength issue.

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