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high-intensity-interval-training-explained

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High Intensity Interval Training Explained

Introduction

Evolutionary History

  • We are evolved to run (when comparing Homo erectus to modern man)
    • Shoulder evolved to stabilize head when running
    • Longer legs, lighter lower legs and forearms to increase efficiency.
    • Lower body shock absorption.
    • Plantar arch provides spring function.
    • Shorter toes decrease the mechanical work involved with running at the cost of gripping capabilities.
    • Improved balance and coordination due to the semicircular canal in the ear.
    • Rapidly moving images now stabilize quicker due to eye adaptation.
    • Gluteus maximus muscles increased in size to stabilize the entire trunk. Large buttocks are only necessary for endurance running.
    • Body hair lost to aid the cooling process.
  • Persistence Hunting
    • Most quadrupeds prey are faster than humans over short distances.
    • Combination of running, walking and tracking to pursue prey until they are exhausted.
    • However, we have an unusually specialized endurance capability.

Who is HIIT for?

  • Basically anyone.
  • Be careful in bulking phases.

HIIT versus Continuous Training

  • Exercise enjoyment
  • Weight loss
    • One study demonstrates that there was no significant difference between CT and control groups.
    • One explanation: CT group had a greater desire to eat than the HIIT group, especially high-fat food.
    • When intensity increases, the total caloric expenditure increases exponentially.
  • Exercise duration
  • Improved fat burning potential
    • The increase in the number of and size of the existing mitochondria
    • Excess Post-Exercise Oxygen Consumption (EPOC), aka the afterburn effect.
    • The elevated level of oxygen consumption will last for several hours.
    • Energy Systems
      • ATP System - used for high-intensity work, less than 10 seconds
      • Glycogen/Lactic Acid System - from 30 seconds up to3 minutes
      • Aerobic System
  • Anaerobic threshold
    • Push back the anaerobic threshold
    • Increasing the anaerobic capacity
  • Beta-endorphin
    • “Feel good” molecule. Might be related with “runners’ high”
    • The higher the intensity, the more beta-endorphin is synthesized
  • Maximal oxygen uptake / VO2 max
  • Athletic performance

HIIT Implementation

HIIT Protocols

  • Interval Training and HIIT
  • Fartlek = Swedish for “speed play”, no markers or times . Ideal for beginners.
  • Little/Gibala protocol (beginner)
    • 60 seconds high-intensity (sub-maximal)
    • 75 seconds recovery
    • Repeat for 8 - 12 cycles
    • Total time: 18 - 27 minutes
  • Tabata (advanced)
    • 20 seconds high-intensity (maximal)
    • 10 seconds recovery
    • Repeat for 8 cycles
    • Total time: 4 minutes

HIIT Intensity

  • Heartrate: HR monitor or Borg scale measuring rate of perceived exertion (RPE), on a scale of 1 - 10, how hard you think you’re working.

Intensity is the reason HIIT works so well, not duration.

  • Suggested intensity of recovery has a broad range: 40-75% maximal HR.

HIIT Duration

Structure HIIT sessions to last a duration of 30 minutes.

  • 30 minutes should be enough to deplete glycogen stores.
  • 30 minutes exclude warm up, cool down and stretches.
  • Aim to progress to decrease recovery period

HIIT Frequency

  • To achieve the best results, have one HIIT session every other day.
  • During bulking, one session of HIIT per week. i.e. HIIT maintenance period.
  • Recent gains of VO2 max in previously untrained individuals are completely lost after a training cessation of only four weeks!
  • In cutting, do it normally.

HIIT Protocols

  • Creating and Recording
    • Create a protocol for each new mode.
    • Work at 100% maximal intensity until exhaustion and record the time taken.
    • Record the duration of the recovery period.
    • Repeat and record the quantity of cycles up to 30 minutes.
  • Progressing
    • Increasing the quantity of cycles (up to 30 minutes)
    • Decreasing the length of recovery period (say, 5 secs at a time)

HIIT Modes

  • Try as many different HIIT modes as possible.

  • Walking

    • Yes, HIIT can be done with walking. Recommended for beginners and those with injuries.
    • This will require a hill or treadmill at steep gradient. Weights can be added.

  • Running

    • This could be dangerous on treadmill, as changing speed is cumbersome.
    • Get around this issue by maintaining moderate speed but using gradients.
    • Gradients should be used as often as possible. Weights can be involved.
    • The moral is: you can always make your sprints more interesting and intense.

  • Cycling

    • Outdoor cycling or stationary bike.
    • Cycling is ideal for HIIT as achieving high intensity is efficient. Many researches on HIIT utilize cycling.
    • Involves legs only.

  • Rowing

    • Utilizes the whole body, hence reaching high intensities can be easy.
    • Best to increasing intensity by increasing stroke rate instead of resistance.
    • Focus on form! Study how to row correctly.

  • Skipping

  • Stair Climbing

  • Stepping

    • Can be carried out literally anywhere
    • Delayed muscular onset soreness (DOMS) when we perform prolonged eccentric movements, i.e. when put down heavy objects.
    • Fatigue caused by concentric exercise can last 24~48 hours, but that by eccentric exercise will last for 48 hours or more.
    • Stretching can reduce the severity of DOMS but not the duration
    • Remember to alternate leading leg!
    • This exercise can be taken every 5 days

  • Swimming

    • Alternate stroke rate
    • Use backstroke for recovery

  • Boxing

    • Use the correct punching techniques to avoid injury.
    • Jogging for recovery

  • Battle Ropes

    • The purest upper body HIIT exercise you can do
    • Waves and Hammers

  • Kettlebells

    • Dynamic stretching beforehand is recommended
    • Clean and Press
      • Begin in a half squat, taking hold of the bell and with a single clean jerk, pull the weight up to the shoulder.
      • Pause for a beat. Then press the weight above your head.
      • Keep a flat back.
    • Full Swing
      • Beginning from a half squat position, swing the bell from between your legs to the arms parallel to the floor position.
      • Larger range can be used.
      • As the weight drops down, bend at the knees and hips, going back into a half squat and swing the bell between the legs.
    • One Arm Snatch
    • Figure 8 Curl
    • Squat and Press
    • Lunge and Press

  • Body weight

    • High Knees
    • Squat Thrusts/Burpees
    • Squat Jumps

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