ATC 351: Know Thyself, How Well Can You Read Your Body’s Signals? Plus: The ‘Gray Zone’ – It Isn’t So Bad If Used Well, Here’s How

April 7, 2023


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Article discussion:

Interoception in Athletes

  • We examine new research on interoception in athletes, and an article in Triathlete Magazine that dissects it further.
  • Study: Interoceptive differences in elite sprint and long-distance runners: A multidimensional investigation
  • Article by Alex Hutchinson: The Case Against Listening To Your Body
  • Interoception vs Intuition:
    • “Interoception” – the felt sense; processing of visceral-afferent neural signals by the central nervous system, which results in the conscious perception of bodily processes. Your brain’s perception of your body’s state, transmitted from receptors on internal organs; i.e. cardiovascular system, lungs, gut, etc. Communication between brain and organs. E.g. being able to tell your HR just by feel without taking pulse.
    • “Intuition” – an inner knowing; the ability to understand something immediately, without the need for conscious reasoning; a hunch or also gut feeling generated by the unconscious mind (experience and cumulative knowledge aids)
  • Hutchinson quote from the article: “It could be that training and competing actually interfere with interoception. Perhaps repeatedly pushing your body beyond its comfortable limits forces you to ignore all the distress signals bombarding your brain. Over time, ignoring them becomes a habit, and you’re less able to judge how you’re feeling. Or perhaps it’s only modern runners whose interoception is impaired, thanks to their reliance on external sources of feedback like GPS watches and heart rate monitors.”
  • The study:
    • Used world-class (ranked in the top 100) sprint and long-distance athletes, and non-athletes. Two questions were addressed:
      • (1) whether sprinters, distance runners and non-athletes differ in their interoceptive abilities, and 
      • (2) whether elite athletes differ from non-elite athletes in their interoceptive abilities. 
    • Study 1: 
      • 213 subjects – 50 sprinters, 67 distance runners, 96 non-athletes
      • 70 elite, 47 non-elite
      • self-reported interoceptive attentional and regulatory styles via online questionnaire (Multidimensional Assessment of Interoceptive Awareness (MAIA) – 32 questions), included anxiety/depression question.
    • Study 2: 
      • 29 athletes: 14 elite (top 100 national rankings), and 15 non-elite (outside top 100 national rankings). There were 17 sprinters (100m, 200m and 400m), 12 distance runners (800–10,000m) and 29 non-athlete controls. Only males?
      • Heart beat counting task and a ‘gold standard’ Heartbeat Detection Task to examine differences in interoceptive accuracy, confidence, and metacognitive awareness. 
      • Two conditions: (i) in silence, and (II) whilst listening to pre-recorded crowd noise that simulated the live sounds of spectators during a sporting event. 
      • Had to report their felt heartbeats and not try to guess or use an exteroceptive aid (such as taking one’s pulse) [44].
      • HDT: The task required participants to judge whether heartbeat sensations are or are not simultaneous with the circle presentation.
      • (I) compared to non-athletes, athletes (i.e., both sprinters and distance runners) had more confidence (Study 2) in their interoceptive percept, and reported trusting their body more, using it to self-regulate and having better attentional control towards their body (Study 1); 
      • (II) sprinters reported having better regulation of attention to internal sensations, more emotional awareness, better self-regulation, and a greater propensity to listen to their body for insight than both distance runners (Fig 3), 
      • (III) athletes (i.e., both sprinters and distance runners) were better able to maintain heartbeat detection performance when distracted compared to non-athletes (Fig 5), and 
      • (IV) elite athletes were characterised by lower emotional awareness, self-regulation, and body listening (Study 1), and were less accurate at counting their heartbeat when not distracted (Fig 4), and characterised by a higher interoceptive prediction error (Study 2). 
    • Good question that was asked by researchers: It should also be considered whether these are innate characteristics of sprint athletes, or a consequence of their participation in high intensity exercise. 
  • It’s complicated though:
    • Inconsistent findings across studies in athletes.
    • It’s so individual because it brings in a lot of life experiences.
    • Interoception (accuracy and/ or awareness) might be related to self-regulation during exercise and athletes may have better interoceptive abilities than non-athletes, but conclusions are limited due to studies taking a unidimensional approach [25], methodological inconsistencies [31, 32]’, and the recruitment of college-level, rather than elite athletes [29, 31, 32]. 
  • Why we would want to “turn off” the ability to feel our body, e.g. during a hard race where we want to check out or dissociate, to mitigate pain, etc.
    • There’s a link between compromised interoceptive function and psychiatric disorders, depression, anxiety, additicion.
    • Mindfulness med improves insular functioning and connectivity to increase interoceoption
    • Insular function correlated with increased empathy
    • Gut feelings: interoceptive sensations, as GI tract responds to emotions and stress
    • Maintaining hameostasis is an interoceptive process
    • Interoceptive signals help us regulate emotional and physical states

Sarah asks:

“The gray zone”

Why does the gray zone (i.e. Z3 range) get such a bad rep if so many programs have us focus on race specificity especially as the goal race nears?

What the coaches say:

  • What they say the problems are:
    • Too easy to be useful and is too hard and too fatiguing
    • When you spend too much or all your time in this zone as many do, esp those not aware of HR, effort/PE, zones, etc.
    • Too much gray Z3 doesn’t help high end sprinting
    • Harder than Z2/MAF so recovery is different—more of it needed, can lead to burout overtraining if too much here
  • What is the Gray Zone:
    • Z3 or tempo is ~2.0-2.5mmol which is quite mild! Put that into context for MOST people and running up a hill puts you in the “grey” zone.
  • But the thing is:
    • Too much Vo2 is also bad.
    • Too much threshold is bad.
    • Too much easy volume is bad.
    • Too much of anything is bad. Duh.Depends on the race distance
    • Depends on the base fitness
    • Depends on how much time before race
    • Everyone responds differently.
  • To consider (the negatives):
    • Athletes tend to do too much and plateau. Should only be ~20% or less of total run volume.
    • For ultra athletes and marathon it is less effective, same as sweetspot. Works better for <70.3, <1/2 marathon.
    • Not good if you use a TRUE polarized or MAF methodology
  • The positives:
    • More stimulation if you are time limited and plateau with the volume you’re able to run.
    • Good mental practice
    • Fun
    • If used sparingly it is fine if you aren’t in a high quality focused block.
    • If you’re very fit and limited on time available
    • If you’re traveling and have very limited time
  • Other Gray zone/Z3 concepts covered:
    • Sweet spot podcast we did.
    • Race specificity–what distances are benefited the most by training at Z3 or in the gray zone?
    • When MAF becomes tempo?
    • Used mostly in a final block as a “specific” intensity. Marathon pace/ effort.
    • ZONES- if you are NOT measuring lactate then everything is on a spectrum. The shift from Z2 into Z3 is very subtle and there isn’t a definite line.
    • Using lactate testing and the polarized method is the exception.
    • No research showing Z3 is better or worse.
    • Some evidence of an increase in mitochondrial density with SS training.
    • Some evidence showing a drop in Vo2 if you do MOSTLY Z3/ SS
    • Everyone responds differentlyBlumenfelt, Iden training ~85% in LT1 the remainder in LT2 or sweetspot/ tempo Still below MLSS
    • ELITE athletes will elicit lower lactate levels at tempo/ Z3 than regular people.

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