Notes on Manipulating High Intensity Training Variables
Manipulating High-Intensity Training Variables
- Based on Larsen and Boucher's textbook, 12 variables can be manipulated to prescribe different HIIT sessions:
- Intensity of the work bout.
- Duration of the work bout.
- Intensity of the recovery bout.
- Duration of the recovery bout.
- Series duration (sets of repetitions).
- Number of series in total.
- Between-series recovery duration.
- Between-series recovery intensity.
- Total volume of the session.
- Training modality (e.g., cycling, running) and ground surface.
- Environmental conditions (e.g., heat, hypoxia).
- Nutritional status of the athlete.
Critical Power/Velocity and Anaerobic Work Capacity
- Anaerobic work capacity (W) can be used across varying intensity-duration combinations.
- Despite different intensity-duration combinations, the total finite volume of W remains the same.
- Example:
- High power/speed: anaerobic work capacity depletes quickly.
- Lower intensity above critical power/velocity: maintained longer, but total anaerobic work capacity is the same.
Recovery Period and Anaerobic Work Capacity
- The recovery period facilitates the recovery of anaerobic work capacity.
- Panel A: Appropriate HIIT session managing anaerobic work capacity.
- Panel B: High-intensity work depletes work capacity toward minimum fatigue.
- Panel C: Long-duration work depletes work capacity toward minimum fatigue.
Active vs. Passive Recovery
- Figure 4.5 shows the effect of active (40% VO2 max) versus passive recovery during a 15-second on, 15-second off HIIT sequence to exhaustion.
- Passive recovery allowed subjects to double their exhaustion time due to higher oxyhemoglobin saturation and lower metabolic rates, compared to active recovery.
- Performing more high-intensity work efforts likely leads to better adaptations. Therefore, passive recovery may be more beneficial.
VO2 and Deoxyhemoglobin During Active vs. Passive Recovery
- Figure 4.6: Mean VO2 and deoxyhemoglobin during six all-out sprints with 21 seconds of active (AR) or passive (PR) recovery.
- VO2 uptake is higher for the AR group.
- Max speed and stride frequency were maintained better for the PR group.
- Maintaining speed and stride frequency during the training session suggests passive recovery might be better.
Influence of Shortened Duration and Active Recovery
- Panel A: Anaerobic work capacity is well-managed.
- Panel B: Shortened recovery duration is insufficient to recover anaerobic work capacity substantially.
- Panel C: Active recovery duration (heightened metabolic rate) reduces the speed of anaerobic work capacity recovery.
Number of Intervals in a Series
- Panel A: Anaerobic work capacity is maintained (e.g., 2 x 4-minute bouts separated by a single series recovery period).
- Panel B: Progression to a more taxing session.
- Panel C: Alternates to sessions A where all series are put together, causing a high amount of fatigue.
Between-Series Recovery Intensity and Duration
- Panel A: Passive and prolonged between-series recovery enhances recovery.
- Panel B: Higher intensity between-series recovery (active recovery) results in less recovery and restoration of anaerobic work capacity.
- Panel C: Shortened between-series recovery duration lowers between-series recovery and anaerobic work capacity.
Considerations for HIIT Programming
- Consider the sport, athlete profile, the place of the training session amongst other training parameters, and phase of training.
- Neuromuscular Load:
- If yes: Program one way.
- If no/low: Consider the modality.
Environmental Conditions
- Heat:
- Impacts body temperature, sweat rate, plasma volume, heart rate, RPE, glycolysis, muscle recruitment, internal/external load ratios, central drive.
- Influences heat shock proteins (adaptations).
- Decreases prolonged exercise and repeated sprint performance.
- Hypoxia:
- Decreases muscle and cerebral oxygenation.
- Increases heart rate for a given workload and RPE, glycolysis rates.
- Increases hypoxic-inducible factor 1-alpha (HIF-1alpha) signaling.
- Increases internal and external load ratio.
- Decreases central neural drive.
- Decreases prolonged exercise or repeat sprint performance.
Nutritional Impact
- Normal environmental and nutritional conditions = typical HIT responses.
- Normal environment + poor nutrition/low glycogen availability = increased AMPK signaling and fat oxidation.
- Caffeine may improve session work capacity.
- Heat: Decreases session mechanical load.
- Fluid restriction: Altered plasma volume responses.
- Hypoxia: Decreased session mechanical load, increased HIF-1alpha signaling.
- Shift from "HIT weapon selection" thinking.
- Ask: What do you want from the HIT session (HIT type and target)?
- How do you achieve it (format weapon)?
- Adjust variables to hit your targets before creating the training session.
HIIT Types and Parameters
- Long Intervals (Types 3 & 4):
- Intensity: 80-85% of velocity of intermittent fitness test; 95-100% of velocity/power of incremental fitness test.
- Work duration: 2-5 minutes per rep.
- Recovery: 1-4 minutes (shorter = passive; longer = ~45% velocity intermittent fitness test).
- Short Intervals (Types 1, 2, 3, & 4):
- Intensity: 90-105% of velocity of intermittent fitness test; 101-120% of final velocity of test.
- Work duration: 10-60 seconds per effort.
- Recovery: 10-60 seconds (shorter = passive; longer = ~45% velocity intermittent fitness test).
- Repeated Sprint Intervals (Types 3 & 4):
- Intensity: All out.
- Work duration: 3-10 seconds per rep.
- Recovery: 15-60 seconds (shorter = passive; longer = ~45%).
- Repeated Sprint Interval (Type 5):
- Intensity: All out.
- Duration: 20-30 seconds.
- Recovery: 1-4 minutes (passive).
- Game-Based HIT Format (Types 2, 3, & 4):
- Self-selected or game-play-related.
- Manipulate number of players, field size, or task constraints.
- Work bouts: 2-5 minutes.
- Recovery: 1:30-2 minutes (passive).
- Variability of response due to gameplay nature.