Monitoring mental fatigue is crucial for optimizing cognitive training, ensuring athletes are adequately challenged without being overloaded. This guide outlines a straightforward protocol using the Psychomotor Vigilance Task - Brief (PVT-B) and the Rating of Mental Fatigue (RMF) scale within Soma Analytics.
Protocol Overview
PVT-B Test Pre-Training: Administer the PVT-B test before starting any cognitive training session. This initial measurement establishes a baseline for the athlete's current level of mental fatigue.
Rating of Mental Fatigue Scale (RMF): Apply the RMF scale within the plan builder. This scale allows athletes to rate their perceived level of mental fatigue after each task, providing valuable feedback on the cognitive load of each activity, including the PVT-B task.
PVT-B Test Post-Training: Conduct the PVT-B test after completing all cognitive tasks for the session. This post-training measurement helps assess the immediate impact of the session on the athlete's mental fatigue and reaction time.
What to Look For: PVT-B
Increase in Reaction Time: A noticeable increase in reaction time on the PVT-B task post-training indicates that an adequate cognitive load was applied during the session. This is a normal and expected outcome when the training effectively challenges the athlete's cognitive capacities.
Lapse Count and Variation: An increase in lapse count (responses slower than 355ms) and variation in reaction times on the PVT-B can also signify that a sufficient cognitive load was applied. It is common to observe increases in both reaction time and lapse count.
Baseline Recovery: Athletes' PVT-B reaction times should return to their baseline or close to it by the next training session. A significant increase in reaction time during the pre-training PVT-B test on any subsequent day may suggest the athlete is still mentally fatigued, indicating a need to adjust the cognitive load or allow more recovery time.
Normal PVT-B Reaction Time: Typical reaction times for the PVT-B range between 180-240ms. Reaction times within this range indicate a normal level of alertness and cognitive readiness.
PVT-B Example
Session | Pre-Session Reaction Time (ms) | Pre-Session Lapses | Post-Session Reaction Time (ms) | Post-Session Lapses |
Session 1 | 180 | 0 | 270 | 2 |
Session 2 | 190 | 0 | 250 | 5 |
Session 3 | 180 | 0 | 240 | 3 |
These results indicate that the training sessions were challenging enough to induce mental fatigue, as evidenced by the increase in reaction time and lapses post-session. The athlete was pushed beyond their baseline cognitive performance, but the consistent return to their baseline pre-session reaction time suggests that the cognitive load was appropriate for their training level.
What to Look For: Mental Fatigue Scale (RMF)
The RMF scale is a critical tool for gauging how challenging an athlete finds a specific task. Utilize this scale to fine-tune your training program:
Task Adjustment: If certain tasks are consistently rated as too easy or too difficult, consider altering the task's placement within the session, adjusting the mode, or modifying the task's intensity or duration.
Deeper Insights: The RMF scale provides deeper insights into the athlete's perception of cognitive load, helping you tailor the cognitive training program to their individual needs and recovery rates.
RMF (Rating of Mental Fatigue) Over 10 Sessions
Session | RMF Rating (0-10) |
Session 1 | 3 |
Session 2 | 4 |
Session 3 | 3 |
Session 4 | 4 |
Session 5 | 5 |
Session 6 | 6 |
Session 7 | 5 |
Session 8 | 6 |
Session 9 | 5 |
Session 10 | 6 |
This table shows RMF ratings fluctuating between sessions but remaining within a manageable range. The variation suggests that while the tasks are challenging, they are not consistently overwhelming, which is ideal for maintaining cognitive resilience. If the ratings remain within this moderate range (3-6), it indicates that the training intensity is appropriate and the athlete is handling the cognitive load well. Regular fluctuations are normal and suggest that the training is challenging the athlete without leading to excessive mental fatigue. This allows for ongoing adjustments to ensure optimal cognitive load and recovery.
Special Considerations
Intentional Overreaching: If implementing a phase of intentional overreaching to push cognitive boundaries, ensure it is followed by a 5-7 day period of reduced cognitive load to allow for adequate recovery. During this phase, it is normal to observe increasing pre PVT-B reaction times across sessions or weeks. This is expected until the overreaching phase is complete.
PVT-B Example - Overreaching
Session | Pre-Session Reaction Time (ms) | Pre-Session Lapses | Post-Session Reaction Time (ms) | Post-Session Lapses |
Session 1 | 180 | 0 | 270 | 2 |
Session 2 | 200 | 2 | 290 | 4 |
Session 3 | 220 | 3 | 310 | 5 |
In this scenario, both the pre-session and post-session reaction times and lapses are increasing with each session. This trend suggests that the athlete may be overreaching as part of a planned training strategy, or they might be struggling with recovery, indicating that adjustments to the training load or recovery protocols may be necessary.
Monitoring Over Time: Establish each athlete's baseline reaction time and mental fatigue levels through consistent monitoring. This longitudinal data is invaluable for adjusting training intensity and ensuring optimal cognitive load throughout training cycles.
PVT-B Over 20 Sessions
Session | Pre-Session Reaction Time (ms) | Pre-Session Lapses | Post-Session Reaction Time (ms) | Post-Session Lapses |
Session 1 | 180 | 0 | 270 | 2 |
Session 2 | 185 | 0 | 265 | 3 |
Session 3 | 180 | 0 | 250 | 1 |
Session 4 | 175 | 0 | 260 | 2 |
Session 5 | 180 | 0 | 255 | 3 |
Session 6 | 178 | 0 | 250 | 2 |
Session 7 | 175 | 0 | 245 | 2 |
Session 8 | 180 | 0 | 260 | 2 |
Session 9 | 182 | 0 | 255 | 3 |
Session 10 | 180 | 0 | 250 | 2 |
Session 11 | 178 | 0 | 245 | 1 |
Session 12 | 176 | 0 | 250 | 2 |
Session 13 | 180 | 0 | 255 | 2 |
Session 14 | 182 | 0 | 250 | 3 |
Session 15 | 180 | 0 | 245 | 2 |
Session 16 | 178 | 0 | 250 | 2 |
Session 17 | 176 | 0 | 255 | 2 |
Session 18 | 180 | 0 | 250 | 3 |
Session 19 | 178 | 0 | 245 | 2 |
Session 20 | 176 | 0 | 250 | 2 |
This table tracks the athlete's reaction time and lapses over 20 sessions, providing a view of their mental fatigue levels. The consistent pre-session reaction times and minimal lapses suggest the athlete maintains stable mental readiness. The variation in post-session data indicates how challenging each session was, helping to adjust training intensity over time. This longitudinal data is crucial for fine-tuning cognitive load and ensuring the athlete's mental fatigue is managed effectively throughout the training cycle.
PVT-B Over 14 Sessions (Indicating Overtraining)
Session | Pre-Session Reaction Time (ms) | Pre-Session Lapses | Post-Session Reaction Time (ms) | Post-Session Lapses |
Session 1 | 180 | 0 | 270 | 2 |
Session 2 | 185 | 1 | 275 | 3 |
Session 3 | 190 | 1 | 280 | 3 |
Session 4 | 195 | 1 | 285 | 4 |
Session 5 | 200 | 2 | 290 | 4 |
Session 6 | 205 | 2 | 295 | 5 |
Session 7 | 210 | 2 | 300 | 5 |
Session 8 | 215 | 3 | 305 | 6 |
Session 9 | 220 | 3 | 310 | 6 |
Session 10 | 225 | 3 | 315 | 7 |
Session 11 | 230 | 4 | 320 | 7 |
Session 12 | 235 | 4 | 325 | 8 |
Session 13 | 240 | 5 | 330 | 8 |
Session 14 | 245 | 5 | 335 | 9 |
In this table, both pre-session and post-session reaction times, along with lapses, are consistently increasing over the 14 sessions. This trend suggests that the athlete is likely experiencing overtraining. The continuous rise in pre-session reaction times indicates inadequate recovery between sessions, while the increasing post-session data reflects accumulating fatigue. Such patterns signal the need to adjust the training load or incorporate more recovery time to prevent further decline in performance and potential injury.
Tips 📝
🔄 Perform the PVT-B test pre- and post-training for every session to establish what is normal for each athlete.
📉 Monitor reaction times: Athletes' reaction times should return to their pre PVT-B baseline or close to it. Over time, you'll identify each athlete's normal range.
⚠️ Reassess cognitive load if pre-training PVT-B reaction times continue to increase each session or week, especially if your goal is not overreaching.
🚧 Expect slower reaction times during a phase of overreaching, as this is a normal part of the overreaching process.
Understanding Lapses as Indicators of Mental Fatigue in Athletes
Lapses in reaction time are critical indicators of mental fatigue in athletes. These lapses represent moments of inattentiveness and delayed responses, reflecting a decline in cognitive function due to fatigue.
How Lapses are Calculated:
Psychomotor Vigilance Test (PVT): A lapse is defined as a response time exceeding 500ms.
PVT-B Test: A response time over 355ms is considered a lapse.
Tracking the number of lapses during cognitive tasks is essential for assessing the level of mental fatigue. An increase in lapse count signals the need for a more detailed examination and potential adjustments in training intensity or recovery protocols.
Key Points to Monitor:
Frequency of Lapses: An increase in the number of lapses indicates rising mental fatigue.
Response Variability: Increased variability in reaction times, along with a higher lapse count, suggests significant cognitive strain.
By understanding and tracking lapses, coaches can gain valuable insights into an athlete’s mental fatigue levels and make necessary adjustments to their cognitive training program.
The Psychomotor Fatigue Threshold Test (PFTT)
The Psychomotor Fatigue Threshold Test (PFTT) is designed to determine the precise moment when an athlete's cognitive responses, especially reaction times, are at their peak during escalating exercise intensities. As physical exertion increases, cognitive performance initially improves, reaching an optimal level. However, past this peak, cognitive signs of fatigue begin to appear, even if the athlete's physical performance endures. This critical point is what the PFTT aims to identify. In essence, it pinpoints the "sweet spot" where an athlete's decision-making is the fastest and most accurate, unaffected by fatigue or cognitive overload.
The table illustrates how cognitive responses improve with increased exercise intensity up to a point, beyond which reaction times begin to slow, indicating that the Psychomotor Fatigue Threshold has been crossed.
Exercise Intensity (%) | Reaction Time (ms) |
20 | 450 |
40 | 400 |
60 | 350 |
70 (Threshold) | 300 |
80 | 450 |
100 | 600 |
How It Works
As physical intensity rises during exercise, cognitive performance initially improves, sharpening until it reaches a peak. Beyond this point, even if the body continues to perform, the brain begins to show signs of fatigue. The Psychomotor Fatigue Threshold Test (PFTT) identifies this critical juncture—the sweet spot where an athlete's decisions are quickest and most accurate, unaffected by fatigue or overload.
Why It's Game-Changing
Complete Performance Picture: The PFTT doesn’t just measure how long or hard an athlete can push; it also evaluates how efficiently their brain functions under increasing exercise intensity, providing a comprehensive view of their overall capabilities.
Training Precision: By identifying this threshold, training can be optimized to extend it, thereby pushing both physical and cognitive boundaries to new limits.
Real-World Benefits: In sports, split-second decisions in high-pressure scenarios are critical. Understanding when an athlete’s cognitive capabilities are at their optimal peak can be invaluable, especially in situations where a fraction of a second can determine victory or defeat.
PVT-B vs. PFTT
The PVT-B (Psychomotor Vigilance Task - Brief) is most effectively used when the primary goal is to monitor mental fatigue. This test is specifically designed to assess how mental fatigue affects cognitive alertness and reaction times. By administering the PVT-B, you can gain detailed insights into an athlete's mental fatigue levels and overall cognitive readiness, making it an essential tool for evaluating how well an athlete can maintain focus and respond to stimuli under conditions of mental strain.
In contrast, the PFTT (Psychomotor Fatigue Threshold Test) is best suited for identifying the precise moment an athlete crosses the psychomotor fatigue threshold during physical training. As physical intensity increases, cognitive performance initially improves, reaching a peak where the brain functions at its highest capacity. However, beyond this peak, cognitive functions, such as reaction time, begin to decline, even if the body continues to perform physically. The PFTT helps pinpoint this critical threshold, allowing coaches to optimize training programs. This might involve keeping the athlete within their optimal performance zone or deliberately pushing them beyond it to enhance their cognitive resilience. Research suggests that this threshold is not fixed and can be improved with consistent, targeted training
When to Use the PVT-B
Monitor Mental Fatigue: Use the PVT-B to assess mental fatigue after cognitive training sessions.
Readiness: Implement this test to evaluate an athlete's mental readiness and detect signs of mental fatigue.
When to Use the PFTT
Identify Psychomotor Fatigue Threshold: Use the PFTT to pinpoint the exact moment an athlete crosses the psychomotor fatigue threshold during physical training.
Optimize Training Programs: Best for determining when cognitive performance peaks and begins to decline as physical intensity rises. This allows you to maintain athletes at their optimal level or push them beyond it to enhance cognitive capacity.
⚠️ Integrated with Physical Training: The PFTT should be used in conjunction with physical training to track cognitive responses under increasing physical stress and to adjust training intensity accordingly based on the threshold identified.