Measurement and Assessment of Training Loads in Sport Science

Introduction to Training Load Measurement and Assessment

• This module (Module 6) focuses on the sport science services aspect of athlete management, specifically the measurement and assessment of training loads.
• It builds upon general points discussed in Module 3, providing a more detailed exploration of the quantification of exercise.
• Use of this material in conjunction with online reading is recommended to support deep conceptual understanding.

Defining Training Load and Its Importance

• Training Load Quantifying: Essential for building an understanding and informing the future prescription of exercise.
• Periodization: Plays a central role in the systematic planning and management of training loads over time.
• Physical Load Categories:
  • External Load: Represents the work prescribed or performed. This encompasses the physical requirements placed on the athlete, such as how fast they run, how hard they work, the duration, and the frequency of efforts.
  • Internal Load: Represents the body's physiological or psychological response to the external load. Typical measures include heart rate response or stress levels.
  • Causal Relationship: External load is necessary to produce the internal load response in the athlete's body.

Formulas for Quantifying Physical and Total Load

• Physical Load: Defined as the product of the volume of a training session and its intensity.
  • $\text{Physical Load} = \text{Volume} \times \text{Intensity}$
• Total Load: Includes the frequency factor to quantify load across a longer time frame, such as a training week.
  • $\text{Total Load} = \text{Volume} \times \text{Intensity} \times \text{Frequency}$

The FITP Principle and External Load Variables

• The FITP principle (Frequency, Intensity, Time, and Type) is used to categorize variables of external load.
• Volume (Time):
  • Total duration of the training session.
  • Total distance covered.
  • Weight lifted (measured in $\text{kilograms}$).
  • Player load (calculated via GPS/accelerometer technology).
• Intensity:
  • Speed (measures such as $\text{km/h}$ or $\text{m/s}$).
  • Percentage of maximum heart rate ($\% \text{HR}_{\text{max}}$).
  • Percentage of maximum oxygen uptake ($\% \text{VO}_2\,max$).
  • Player load rate (player load per minute).
• Frequency:
  • Number of efforts within a session or set.
  • Number of training sessions over a specific time frame.
• Type:
  • Modifications including altitude training, modality (bike, running, swimming), or environmental conditions (hot and humid conditions).

Technological Measurement of External Load

• Power Output:
  • Measured in total Watts ($W$).
  • Laboratory Measurement: Conducted on specialized bikes, such as those found in Deakin laboratory facilities.
  • Field Measurement: Recent technology allows for portable power output assessment.
• Global Positioning Systems (GPS):
  • Modern technology can run at $15\,\text{Hz}$, translating to $15$ data points collected per second.
  • Large data sets: A $3$-hour match in Australian football results in massive data volumes due to the frequency of sampling across a whole team.
  • Accessibility: Smartwatches and fitness trackers have made tracking distance and movement accessible to the general public.

Internal Load Variables: Objective and Subjective Categories

• Objective Measures:
  • Heart rate (beats per minute, percentages of maximum, or reserve heart rate).
  • Reserve or maximum oxygen uptake ($\text{VO}_2\,\text{max}$).
  • Blood lactate levels.
• Subjective Measures:
  • Rating of Perceived Exertion (RPE).
  • Session Rating of Perceived Exertion (sRPE).
  • Questionnaires regarding athlete status.
  • Direct observation by coaches or scientists.

Training Zones and Exercise Prescription

• Zone Selection: Established heart rate and intensity zones allow for precise exercise prescription.
• Continuous and Long Duration Exercise: Prescribed based on heart rate max, heart rate reserve, and specific fuel system utilization.
• High-Intensity Exercise: Scale adapted for anaerobic-concentrated efforts, such as high-intensity interval training (HIIT).
• Balance: Using these zones ensures that preparation aligns with the periodized plan, allowing practitioners to compare planned intensity versus actual completed intensity.

Heart Rate Monitoring as a Physiological Gauge

• Heart rate provides a key physiological response to effort, indicating the stress placed on the cardiovascular system.
• Primary Uses:
  • Gauging intensity and effort for a specific exercise bout.
  • Reflecting the training environment; for example, exercising in the heat typically causes a more pronounced heart rate response (higher heart rate at a given intensity).
  • Identifying overtraining risks: A \"numb response\" (slow heart rate recovery or slow response to exercise onset) acts as an indicator of excessive fatigue.
  • Monitoring sport-specific requirements and educating the athlete.
  • Serving as a motivational tool to encourage harder training.
• Biological Factors:
  • Heart rate is genetically determined.
  • Maximum heart rate decreases with age.
  • There can be a variance of up to $20$ beats between individuals of the same age.
• Prediction Formulas:
  • The traditional $220 - \text{age}$ formula is outdated and not recommended for precise measurement.
  • A newer equation (though not named) is cited as having a stronger relationship with predicting true heart rate max.
  • The gold standard is a staged maximal test (like a VO2 max test), where the heart rate at the point of exhaustion is the true peak.

Quantifying Physiological Load: TRiMP and Blood Lactate

• TRiMP Method (Training Impulse):
  • Calculated as the average heart rate multiplied by the duration of the session.
  • $\text{TRiMP} = \text{Average Heart Rate} \times \text{Time}$
• Time in Zone: An alternative approach involves quantifying the exact minutes spent in various heart rate intensity zones.
• Blood Lactate Monitoring:
  • Samples are collected from the finger or ear lobe.
  • Assumes blood levels represent muscle lactate (where production occurs).
  • Comparison: Endurance-trained athletes show a delayed lactate threshold response to ramped exercise compared to non-trained individuals.

Subjective Assessment: Rating of Perceived Exertion (RPE)

• Originally developed in the $1960\text{s}$, RPE is highly effective and correlates closely with heart rate response.
• Advantages: Affordable, requires no equipment, and is highly adaptable.
• Common Scales:
  • Borg Scale ($6$ to $20$ scale).
  • Modern and predominant scale ($1$ to $10$ scale).
  • Traditional Scale ($0$ to $10$), which is exponential in nature.
• Implementation Requirements:
  • Education and familiarization for the athlete are mandatory to ensure validity.
  • Must account for external factors like fatigue, illness (\"feeling under the weather\"), or harsh environmental conditions that skew perceptions.

Practical Implementation: Session RPE (sRPE) and Records

• Session RPE Calculation:
  • Internal load is quantified in arbitrary units (AU).
  • $\text{sRPE} = \text{RPE Descriptor} \times \text{Session Duration (minutes)}$
• Management Strategy:
  • Monitoring should be systematic and progressive.
  • Training load and response should be measured for every session to maintain accurate records.
  • While load is measured daily, fatigue and mood metrics are often captured on a weekly or monthly basis.
  • Maintaining a regular record is central to effective athlete management and future prescription planning.