Random thoughts on MDPs_Defining groups and possible testing solutions_Part_3

In Part 1 and Part 2 (https://www.dhirubhai.net/pulse/random-thoughts-most-demanding-period-football-2-marko-matu?inskij-xdmbf/), I explored some possible solutions for defining Most Demanding Periods (MDPs) and how they can be detected. Initially, I used ChatGPT to structure ideas around three types of MDPs, but there were some inconsistencies in variable allocation. Now, in Part 3, I’ll refine the classification and provide a clearer perspective on where each variable should be placed within the oxidative, glycolytic, and neuromuscular components.

Oxidative (Aerobic) Component

The oxidative component represents the aerobic energy system, responsible for sustained, lower-to-moderate intensity efforts. It is characterized by continuous movement with relatively low neuromuscular strain. This system is essential for maintaining a player’s work rate and ability to recover between high-intensity bouts.

Characteristics:

Continuous running with limited high-speed efforts. ? Enables recovery of W′ when the player operates below CP (Critical Power). ? Supports longer-duration efforts at moderate intensities. ? Minimal neuromuscular fatigue compared to glycolytic and mechanical loads.

Key Variables:

• Total Distance (m): Represents overall workload and endurance capacity.
• Distance Covered per Minute (m/min): Quantifies aerobic work intensity if number of acc and dec is low
• Heart Rate (%HRmax): Monitors internal cardiovascular load.
• Work-to-Rest Ratio: Identifies sustained effort relative to recovery periods.
• Metabolic Power (Moderate levels, ~5–10 W/kg): Indicates continuous moderate-intensity work.

Reserve and Consumption Relationship:

• When active: Low W′ consumption; the player sustains movement below CP.
• During recovery: Primary mechanism for replenishing W′ after high-intensity phases.

Glycolytic (Metabolic) Component

The glycolytic system covers anaerobic metabolism, fueling high-intensity efforts lasting 30 seconds to 2 minutes. It bridges efforts that are too intense for the aerobic system but not short enough to rely solely on neuromuscular explosiveness.

Characteristics:

? Key system for repeated sprint efforts and pressing actions. ? High lactate accumulation, leading to increased fatigue. ? Involves frequent stop-start movements with a mix of acceleration and deceleration (but in higher density of it). ? Supports anaerobic endurance rather than maximal explosiveness.

Key Variables:

• Number of Accelerations (>2–3 m/s2): Indicates metabolic strain from repeated bursts with lower rest rations between actions.
• Number of Decelerations (>2–3 m/s2): Adds to metabolic load through stop-start movement with lower rest rations between actions.
• Metabolic Power (High levels, >10 W/kg): Reflects high-energy anaerobic activity.
• Player Load (Arbitrary Units): Measures cumulative external load.
• Explosive Accelerations/Decelerations (>3 m/s2): Highlights metabolic demand in high-intensity bursts with lower rest rations between actions.

Reserve and Consumption Relationship:

• When active: W′ consumption is moderate to high, depending on sprint intensity and density of efforts.
• During recovery: Partial replenishment occurs during submaximal activity but is slower than oxidative recovery.

Neuromuscular (Mechanical) Component

Definition:

The neuromuscular (mechanical) component refers to explosive, short-duration efforts (≤10 seconds), such as sprints, jumps, and rapid changes of direction. These actions place a significant mechanical load on the muscles, tendons, and nervous system.

? High-intensity, short-duration actions (sprints, jumps, cutting movements). ? High mechanical strain due to rapid force application. ? Can lead to significant W′ depletion if repeated frequently - goes to glycolytic .

Key Variables:

• High-Speed Running (HSR) Distance (>19.8 km/h): Reflects high-speed neuromuscular actions.
• Sprint Distance (>25 km/h): Measures explosive sprint output.
• HSR per Minute & Sprint Distance per Minute: Normalize sprinting efforts over time.
• High Accelerations and Decelerations (>3 m/s2): Indicate mechanical stress on the body with more recovery between actions
• Jump Metrics (if available): Capture neuromuscular explosiveness.

Reserve and Consumption Relationship:

• When active: W′ depletes rapidly during short bursts of maximal effort.
• During recovery: Neuromuscular system requires extended rest or low-intensity movement for full restoration

This is just a theoretical model, and for me, the problem with this approach is the exact division between glycolytic and neuromuscular strain. The model should take into account the frequency and density of actions. For example, a single high-intensity acceleration and deceleration might belong to the neuromuscular zone, but if this action is repeated in transitions during a game or small-sided exercises, it shifts to the glycolytic system.

I like how Mladen Jovanovi? calls himself a complementarist. As I get older, I find myself thinking in a similar way—there is always something on the other end. In our profession, we often see people sticking to one methodology while others promote the opposite. I prefer to think that both can be valid depending on context and situation.

Defining Player Profiles in Most Demanding Periods (MDPs)

As we have detected the MDP parts, one missing aspect is understanding how they occur during the game. Since I am still waiting for data analysis from partners, I will move forward with the next step: defining player profiles in these MDPs.

To classify players based on their oxidative, neuromuscular, and glycolytic capabilities, we need a structured testing approach. Below are the recommended tests, their key variables, and why they are important for football performance.

Oxidative (Aerobic) Profile Tests

The oxidative system determines a player’s ability to sustain prolonged efforts and recover efficiently between high-intensity actions. This is crucial for players who cover large distances and maintain a high work rate throughout the game.

Recommended Tests:

30-15 Intermittent Fitness Test (30-15 IFT) (Buchheit, 2008)

• Variable: Final velocity reached (VIFT)
• Why? Strong correlation with Critical Power (CP), which defines the threshold between sustainable and unsustainable efforts. Players with a higher VIFT can maintain higher running speeds over long periods.

Yo-Yo Intermittent Recovery Test Level 1 & 2 (Bangsbo, 1994)

• Variable: Total distance covered.
• Why? A key indicator of a player’s ability to recover between repeated high-intensity bouts. Higher values indicate better aerobic endurance and ability to sustain transitions and pressing actions.

Submaximal Heart Rate Recovery Test (Impellizzeri et al., 2005)

• Variable: Heart Rate (HR) drop post-exercise
• Why? Faster HR recovery indicates better autonomic nervous system efficiency, which allows for quicker recovery between MDP phases.

?? Application: Players with high oxidative capacity are well-suited for roles that require constant running, high work rates, and pressing strategies (e.g., box-to-box midfielders, full-backs).

Glycolytic (Metabolic) Profile Tests

The glycolytic system is responsible for repeated high-intensity efforts, such as sprinting, pressing, and transition play. These tests assess how well a player sustains explosive movements over multiple repetitions.

Recommended Tests:

Repeated Sprint Ability (RSA) Test (Girard et al., 2011)

• Variable: Sprint decrement (%)
• Why? Indicates how much performance drops after repeated sprints. Players with a low sprint decrement can sustain high-speed efforts with less fatigue.

Wingate Anaerobic Test (Bar-Or, 1987)

• Variable: Peak Power Output (W/kg)
• Why? Measures anaerobic capacity and ability to generate explosive power in short bursts. Critical for players involved in high-intensity pressing or counter-attacks.

High-Intensity Interval Drill Analysis (GPS-Based) (Stevens et al., 2017)

• Variable: Number of accelerations & decelerations (>2.5 m/s2)
• Why? Reflects metabolic demands of repeated stop-start actions, key for wingers, attacking midfielders, and defenders in pressing systems.

Application: Players with high glycolytic capacity are ideal for positions that require constant bursts of acceleration and deceleration, such as wingers, attacking midfielders, and aggressive defenders.

Neuromuscular (Mechanical) Profile Tests

The neuromuscular system is responsible for explosive, high-power movements, such as sprinting, jumping, and rapid directional changes. These tests assess a player’s ability to generate force quickly and tolerate high mechanical loads.

Recommended Tests:

Countermovement Jump (CMJ) & Squat Jump (SJ) (Bosco et al., 1983)

• Variable: Jump height (cm)

Sprint Test (10m, 20m, 30m) (Haugen et al., 2012)

• Variable: Sprint time (s)
• Why? Shorter times indicate better acceleration ability, which is critical for strikers, full-backs, and wingers.

Nordic Hamstring Test (Mj?lsnes et al., 2004)

• Variable: Force output (N)
• Why? High force values indicate better eccentric hamstring strength, reducing injury risk and improving sprint performance.

Application: Players with high neuromuscular capacity excel in positions where explosiveness and reactivity are critical, such as strikers, wingers, and defenders making last-ditch tackles.

Integrating Testing with MDP Profiles

Once testing is complete, we can classify players into MDP-specific profiles:

1?? Endurance-Dominant Player → High CP, good Yo-Yo IR scores, moderate sprint capacity. Best for maintaining high work rates.

2?? Explosive Sprinter → High sprint speeds and CMJ scores, but lower endurance. Best for counter-attacks and quick transitions.

3?? Repeated Effort Specialist → Strong RSA performance, balancing anaerobic and aerobic systems. Key for high-intensity pressing roles.

4?? Mechanical Load Tolerant → High neuromuscular scores (HSR, sprints per game), capable of sustaining high-intensity mechanical stress.

Positional Classification Based on Player Profiles

Each position has different physical demands and can fit into multiple Most Demanding Periods (MDP) profiles based on their playing style and tactical role. Below is a breakdown of where each position fits within the four profiles, along with which tests should be emphasized for optimal performance development.

Position-to-Profile Mapping

Focused Testing Per Position

Explanation of Position-Specific Testing Priorities

Endurance-Dominant Players (Full-Backs, Central Midfielders)

• Emphasis: Aerobic fitness, ability to sustain high work rates
• Key Tests: 30-15 IFT, Yo-Yo IR, RSA Test
• Why? These players must cover large distances and sustain high-intensity movement throughout the game.

Explosive Sprinters (Wingers, Strikers, Attacking Midfielders)

• Emphasis: Speed, acceleration, quick changes of direction
• Key Tests: Sprint Tests (10m, 20m, 30m), CMJ, RSA Test
• Why? These players thrive in transition moments, often making explosive movements to attack spaces.

Repeated Effort Specialists (Defensive Midfielders, Some Full-Backs, Attacking Midfielders)

• Emphasis: Repeated sprint ability, endurance, pressing efficiency
• Key Tests: RSA Test, Sprint Test (10m), Yo-Yo IR
• Why? These players frequently engage in high-intensity pressing and need fast recovery between bursts.

Mechanical Load Tolerant (Center-Backs, Some Strikers, Goalkeepers)

• Emphasis: Strength, power, injury prevention
• Key Tests: CMJ, Hop Test, Nordic Hamstring Test
• Why? These players must tolerate high mechanical loads from duels, jumps, and sprinting.

This approach does not mean that we should exclude other tests, but rather prioritize certain tests when analyzing the results for different positions. Every player should be tested across all physical qualities at the beginning of the preseason to establish a baseline profile. However, when implementing in-season flexible testing or mid-season assessments, we can focus more on the recommended tests that align with the player's positional profile and performance needs.

By using a flexible testing approach, we ensure that players are continually monitored and developing the right physical attributes, without overloading them with unnecessary tests. This makes performance analysis more efficient and targeted, leading to better training adaptations and injury prevention strategies.

Structuring Flexible Testing Schedules in the Training Cycle

A structured yet flexible testing schedule ensures that players are monitored throughout the season without interfering with performance or causing unnecessary fatigue. Below is a framework for integrating full assessments, in-season flexible testing, and position-specific evaluations.

Preseason: Full Baseline Testing

Goal: Establish a comprehensive profile for each player.

Timing: First 1-2 weeks of preseason.

Tests Included:

Aerobic Capacity (Oxidative System): 30-15 IFT, Yo-Yo IR1/2

Anaerobic Capacity (Glycolytic System): RSA Test, Sprint Decrement

Explosiveness & Strength (Neuromuscular System): CMJ, Squat Jump, Hop Test

Sprint & Acceleration: 10m, 20m, 30m Sprint Test Injury Prevention: Nordic Hamstring Test

Application:

• These results set benchmarks for the season-long monitoring plan.
• Players are categorized based on MDP profiles to personalize load management.

In-Season Flexible Testing (Every 4-6 Weeks)

Goal: Monitor fatigue, adaptations, and weaknesses without disrupting training.

Full-Backs & CMs : 30-15 IFT or Yo-Yo IR1/2 : Track endurance drop-off

Wingers & Strikers:RSA, Sprint Test (20m, 30m), CMJ: Monitor speed & power levels

Defensive Mids: RSA Test, 10m Sprint: Ensure repeated sprint capacity

Center-Backs: CMJ, Nordic Hamstring: Injury prevention, jump ability

Goalkeepers: Sprint 10m, CMJ, Hop Test: Explosiveness for diving & reactions

Application:

• Tests should be short (~10-15 min), embedded before training
• Instead of testing everything, focus on 1-2 key metrics per testing session.

End-of-Season Evaluation

Goal: Measure long-term adaptations and prepare for off-season development. Timing: Final 2-3 weeks of the season.

Tests Included: Full Battery of Preseason Tests for progress tracking. Position-Specific Focus Tests to determine off-season priorities.

Application:

• Review which training programs worked best for each MDP profile.
• Use data to guide individualized off-season training programs.
• Plan return-to-play strategies for players recovering from injuries