Mental Fatigue, Mindfulness Training, Neurocognitive Function, Sports Performance
Conditions
Keywords
Mindfulness Training, Mental Fatigue, Inhibitory Control, Endurance Performance, ERP
Brief summary
Mental fatigue has been suggested that would impair neurocognitive functions and sports performance. On the other hand, mindfulness training (MT) seems to as a promising approach to attenuate mental fatigue and counteract its detrimental effect on cognitive functions and sports performance. The purpose of the present study is to examine the effect of MT on behavioral and neuroelectric indices of inhibitory control, and endurance performance in mentally fatigued athletes.
Detailed description
Accumulating research indicates that mental fatigue induced by prolonged cognitive tasks would impair neurocognitive functions and sports performance. Additionally, recent studies demonstrate that inhibitory control and endurance performance are significantly susceptible to detrimental effects of mental fatigue. On the other hand, mindfulness training (MT) has been widely been used to enhance cognitive functions and sports performance in neurocognitive and sports research, which has been considered a promising approach for attenuating mental fatigue and counteracting the detrimental effect of mental fatigue. However, the effect of MT on inhibitory control, endurance performance, and underlying mechanisms in mentally fatigued athletes remain unclear. Therefore, the purpose of the present study is to examine the effect of MT on behavioral and neuroelectric indices of inhibitory control, and endurance performance in mentally fatigued athletes. Specifically, the targeted primary outcomes are neurocognitive functions (i.e., reaction time, accuracy and ERPs in Flanker task) and endurance performance (i.e., VO2max & time to exhaustion); The secondary outcomes are changes in dispositional mindfulness, subjective (i.e., scores in visual analog scale)/objective (i.e., reaction time, accuracy in Stroop task) mental fatigue, motivation in tasks, and changes in mood state (i.e., BRUMS-C).
Interventions
BEHAVIORALMindfulness intervention
The mindfulness program called Mindfulness-based peak performance (MBPP) will be used in this study. MBPP is a program that consists of eight 60-min training, and a 60-min session weekly for 8-weeks. The MBPP program will include (1) 5 minutes of will start with a brief recap of the preceding session and homework discussion, (2) after which the 5 minutes of a brief story about performance aimed at inducing the learning motivation of the participants; (3) Followed by 20 minutes of a theoretical lecture introducing a new topic and then (4) 25 minutes of mindfulness exercise. (5) Finally, how to apply the mindfulness skills to sports context will be discussed at the end of each session for 5 minutes.
Sponsors
National Taiwan Normal University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 25 Years
Healthy volunteers
Yes
Inclusion criteria
1. Regular sports training at least 4 hours weekly 2. Normal or corrected-to-normal vision 3. Right-handed
Exclusion criteria
1. Physical limitation or injury in lower limbs before and during the study 2. Diagnosed or self-reported neurological disorders (e.g., epilepsy) 3. Diagnosed or self-reported major psychiatric illness (e.g., major depression, schizophrenia) 4. Major previous experience with mindfulness training
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Inhibitory Control: Reaction Time | After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks) | Followed by the manipulation conditions, inhibitory control will be evaluated by a Flanker task (i.e., either mental fatigue condition or control condition). In the Flanker task, participants will be presented with five arrows and will be instructed to respond as quickly and accurately as possible to the direction where the middle arrow is pointing (i.e., left or right). Types of trials are the congruent (i.e., \> \> \> \> \>) and incongruent (i.e., \< \< \> \< \<). The reaction time (RT) and accuracy (ACC) of the incongruent trials were calculated as inhibitory control performance, and the difference between conditions was further calculated to represent a mental fatigue-related impairment of inhibitory control in pre-test and post-test. |
| Inhibitory Control: Accuracy | After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks) | Followed by the manipulation conditions, inhibitory control will be evaluated by a Flanker task (i.e., either mental fatigue condition or control condition). In the Flanker task, participants will be presented with five arrows and will be instructed to respond as quickly and accurately as possible to the direction where the middle arrow is pointing (i.e., left or right). Types of trials are the congruent (i.e., \> \> \> \> \>) and incongruent (i.e., \< \< \> \< \<). The reaction time (RT) and accuracy (ACC) of the incongruent trials were calculated as inhibitory control performance, and the difference between conditions was further calculated to represent a mental fatigue-related impairment of inhibitory control in pre-test and post-test. |
| ERP: N2 | After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks) | The neuroelectrical activities (i.e., N2, P3) during the Flanker task were recorded and analyzed using the Neuroscan system. The difference in neuroelectrical activities between conditions (i.e., mental fatigue condition & control condition) were calculated as mental fatigue-related impairment in neuroelectrical markers of inhibitory control. |
| ERP: P3 | After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks) | The neuroelectrical activities (i.e., N2, P3) during the Flanker task were recorded and analyzed using the Neuroscan system. The difference in neuroelectrical activities between conditions (i.e., mental fatigue condition & control condition) were calculated as mental fatigue-related impairment in neuroelectrical markers of inhibitory control. |
| Endurance Performance: Time to Exhaustion | After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks) | The graded exercise test (GXT) on treadmill was used to assess participant's endurance performance. Bruce protocol will be adopted in the test. The initial speed and grade of the GXT will be set at 2.74 km/hr with a grade of 10% and increase speed and grade every 3 min until participants are voluntarily exhausted. The time to exhaustion (TTE) was recorded as the endurance performance. The difference in TTE between conditions was further calculated (i.e., control condition minus mental fatigue condition) for both the pre-test and post-test. |
| Endurance Performance: VO2max | After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks) | The graded exercise test (GXT) on treadmill was used to assess participant's endurance performance. Bruce protocol will be adopted in the test. The initial speed and grade of the GXT will be set at 2.74 km/hr with a grade of 10% and increase speed and grade every 3 min until participants are voluntarily exhausted. The maximum oxygen consumption (VO2 max) was recorded as the endurance performance. The difference in VO2max between conditions was further calculated (i.e., control condition minus mental fatigue condition) for both the pre-test and post-test. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Mood State: Fatigue | Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks) | Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher fatigue mood. |
| Mood State: Tension | Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks) | Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher tension mood. |
| Subjective Mental Fatigue | Before, after 30-minute Stroop task and after Flanker task in the mental fatigue and control condition at pre-test and post-test (8 weeks) | Both in the baseline and post-intervention, the visual analog scale for mental fatigue (VAS-MF) was used to assess changes in subjective mental fatigue before and after experimental manipulation. The scale ranges from 0 (not at all mentally fatigued) to 100 (extremely mentally fatigued). |
| Perception of Effort | every 2.5 minutes during graded exercise test | During the graded exercise test, the perception of effort will be asked at beginning and every 2.5-min using Borg 6 to 20 scale, until the participant comes to voluntary exhaustion. |
| Mood State: Vigour | Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks) | Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher vigor mood. |
| Objective Mental Fatigue | Post 30-minute mental fatigue and control condition at pre-test and post-test (8 weeks) | Both at baseline and post-intervention, participants completed either a 30-min 100% incongruent version Stroop task (i.e., mental fatigue condition) or a 30-min 100% congruent version Stroop task (i.e., control condition). In the Stroop task, accuracy (ACC) was calculated as an index of objective mental fatigue. It is expressed as a percentage, determined by dividing the number of correct responses by the total number of responses. |
| Dispositional Mindfulness | Baseline (pre-test) and 8 weeks (post-test) | The change in dispositional mindfulness was assessed using the 16-item (5-Likert scale) athlete mindfulness questionnaire (AMQ). The mean score range is between 1-5. Higher mean scores indicate a higher level of dispositional mindfulness. |
| Mood State: Anger | Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks) | Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher anger mood. |
| Mood State: Confusion | Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks) | Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher confusion mood. |
| Mood State: Depression | Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks) | Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher depression mood. |
Countries
Taiwan
Participant flow
Pre-assignment details
No participants were excluded from the study before assignment to groups.
Participants by arm
| Arm | Count |
|---|---|
| Mindfulness Training Group Participants in the mindfulness training (MT) group will engage in a 60-min session of mindfulness program per week for 8 weeks.
Mindfulness intervention: The mindfulness program called Mindfulness-based peak performance (MBPP) will be used in this study. MBPP is a program that consists of eight 60-min training, and a 60-min session weekly for 8-weeks. The MBPP program will include (1) 5 minutes of will start with a brief recap of the preceding session and homework discussion, (2) after which the 5 minutes of a brief story about performance aimed at inducing the learning motivation of the participants; (3) Followed by 20 minutes of a theoretical lecture introducing a new topic and then (4) 25 minutes of mindfulness exercise. (5) Finally, how to apply the mindfulness skills to sports context will be discussed at the end of each session for 5 minutes. | 26 |
| Waitlist Control Group Participants in the waitlist control group will be required to maintain regular life and routine training. Once the participants in control group finished the whole experiment, they will be invited to participate in the MBPP program for eight weeks. | 27 |
| Total | 53 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Did not receive intervention | 1 | 0 |
| Overall Study | Lost to Follow-up | 3 | 3 |
Baseline characteristics
| Characteristic | Waitlist Control Group | Total | Mindfulness Training Group |
|---|---|---|---|
| Age, Continuous | 20.22 years STANDARD_DEVIATION 1.5 | 20.15 years STANDARD_DEVIATION 1.42 | 20.08 years STANDARD_DEVIATION 1.35 |
| Education level | 14.44 years STANDARD_DEVIATION 1.4 | 14.40 years STANDARD_DEVIATION 1.35 | 14.35 years STANDARD_DEVIATION 1.32 |
| Height | 168.72 centimeter (cm) STANDARD_DEVIATION 6.62 | 168.12 centimeter (cm) STANDARD_DEVIATION 6.75 | 167.5 centimeter (cm) STANDARD_DEVIATION 6.96 |
| Race and Ethnicity Not Collected | — | 0 Participants | — |
| Sex: Female, Male Female | 5 Participants | 12 Participants | 7 Participants |
| Sex: Female, Male Male | 22 Participants | 41 Participants | 19 Participants |
| Sport Judo | 7 Participants | 12 Participants | 5 Participants |
| Sport Track & field | 7 Participants | 14 Participants | 7 Participants |
| Sport Wrestling | 6 Participants | 11 Participants | 5 Participants |
| Sport Wushu | 7 Participants | 16 Participants | 9 Participants |
| Training experience | 8.18 years STANDARD_DEVIATION 2.65 | 8.10 years STANDARD_DEVIATION 2.39 | 8.00 years STANDARD_DEVIATION 2.06 |
| Weight | 66.88 kilograms (kg) STANDARD_DEVIATION 10.01 | 69.17 kilograms (kg) STANDARD_DEVIATION 20.07 | 71.55 kilograms (kg) STANDARD_DEVIATION 26.88 |
| Working memory Backward digit span | 10.22 units on a scale STANDARD_DEVIATION 2.45 | 9.75 units on a scale STANDARD_DEVIATION 2.62 | 9.27 units on a scale STANDARD_DEVIATION 2.75 |
| Working memory Forward digit span | 14.22 units on a scale STANDARD_DEVIATION 1.55 | 14.28 units on a scale STANDARD_DEVIATION 1.78 | 14.35 units on a scale STANDARD_DEVIATION 2.02 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 26 | 0 / 27 |
| other Total, other adverse events | 0 / 26 | 0 / 27 |
| serious Total, serious adverse events | 0 / 26 | 0 / 27 |
Outcome results
Primary
Endurance Performance: Time to Exhaustion
The graded exercise test (GXT) on treadmill was used to assess participant's endurance performance. Bruce protocol will be adopted in the test. The initial speed and grade of the GXT will be set at 2.74 km/hr with a grade of 10% and increase speed and grade every 3 min until participants are voluntarily exhausted. The time to exhaustion (TTE) was recorded as the endurance performance. The difference in TTE between conditions was further calculated (i.e., control condition minus mental fatigue condition) for both the pre-test and post-test.
Time frame: After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Endurance Performance: Time to Exhaustion | Condition difference in TTE at pre-test | 28.50 second | Standard Deviation 32.28 |
| Mindfulness Training Group | Endurance Performance: Time to Exhaustion | Condition difference in TTE at post-test | -20.06 second | Standard Deviation 33.54 |
| Waitlist Control Group | Endurance Performance: Time to Exhaustion | Condition difference in TTE at pre-test | 23.89 second | Standard Deviation 36.43 |
| Waitlist Control Group | Endurance Performance: Time to Exhaustion | Condition difference in TTE at post-test | 13.15 second | Standard Deviation 34.45 |
p-value: <0.01ANCOVA
Primary
Endurance Performance: VO2max
The graded exercise test (GXT) on treadmill was used to assess participant's endurance performance. Bruce protocol will be adopted in the test. The initial speed and grade of the GXT will be set at 2.74 km/hr with a grade of 10% and increase speed and grade every 3 min until participants are voluntarily exhausted. The maximum oxygen consumption (VO2 max) was recorded as the endurance performance. The difference in VO2max between conditions was further calculated (i.e., control condition minus mental fatigue condition) for both the pre-test and post-test.
Time frame: After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Endurance Performance: VO2max | Condition difference in VO2max at pre-test | 0.86 ml/kg/min | Standard Deviation 4.88 |
| Mindfulness Training Group | Endurance Performance: VO2max | Condition difference in VO2max at post-test | -0.16 ml/kg/min | Standard Deviation 2.92 |
| Waitlist Control Group | Endurance Performance: VO2max | Condition difference in VO2max at pre-test | 0.92 ml/kg/min | Standard Deviation 4.12 |
| Waitlist Control Group | Endurance Performance: VO2max | Condition difference in VO2max at post-test | -0.02 ml/kg/min | Standard Deviation 3.62 |
p-value: >0.05ANCOVA
Primary
ERP: N2
The neuroelectrical activities (i.e., N2, P3) during the Flanker task were recorded and analyzed using the Neuroscan system. The difference in neuroelectrical activities between conditions (i.e., mental fatigue condition & control condition) were calculated as mental fatigue-related impairment in neuroelectrical markers of inhibitory control.
Time frame: After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | ERP: N2 | Condition difference in N2 amplitude at pre-test (incongruent trial) | -1.27 μV | Standard Deviation 3.48 |
| Mindfulness Training Group | ERP: N2 | Condition difference in N2 amplitude at post-test (incongruent trial) | 0.72 μV | Standard Deviation 4.07 |
| Waitlist Control Group | ERP: N2 | Condition difference in N2 amplitude at pre-test (incongruent trial) | -1.14 μV | Standard Deviation 4.85 |
| Waitlist Control Group | ERP: N2 | Condition difference in N2 amplitude at post-test (incongruent trial) | 0.18 μV | Standard Deviation 2.58 |
p-value: >0.05ANCOVA
Primary
ERP: P3
The neuroelectrical activities (i.e., N2, P3) during the Flanker task were recorded and analyzed using the Neuroscan system. The difference in neuroelectrical activities between conditions (i.e., mental fatigue condition & control condition) were calculated as mental fatigue-related impairment in neuroelectrical markers of inhibitory control.
Time frame: After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | ERP: P3 | Condition difference in P3 amplitude at pre-test (incongruent trial) | -0.28 μV | Standard Deviation 3.85 |
| Mindfulness Training Group | ERP: P3 | Condition difference in P3 amplitude at post-test (incongruent trial) | 0.78 μV | Standard Deviation 6.05 |
| Waitlist Control Group | ERP: P3 | Condition difference in P3 amplitude at pre-test (incongruent trial) | 0.19 μV | Standard Deviation 5.23 |
| Waitlist Control Group | ERP: P3 | Condition difference in P3 amplitude at post-test (incongruent trial) | -0.69 μV | Standard Deviation 5.6 |
p-value: >0.05ANCOVA
Primary
Inhibitory Control: Accuracy
Followed by the manipulation conditions, inhibitory control will be evaluated by a Flanker task (i.e., either mental fatigue condition or control condition). In the Flanker task, participants will be presented with five arrows and will be instructed to respond as quickly and accurately as possible to the direction where the middle arrow is pointing (i.e., left or right). Types of trials are the congruent (i.e., \> \> \> \> \>) and incongruent (i.e., \< \< \> \< \<). The reaction time (RT) and accuracy (ACC) of the incongruent trials were calculated as inhibitory control performance, and the difference between conditions was further calculated to represent a mental fatigue-related impairment of inhibitory control in pre-test and post-test.
Time frame: After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Inhibitory Control: Accuracy | Condition difference in ACC of Flanker task (pre-test) | 6.15 percentage of correct response | Standard Deviation 11.79 |
| Mindfulness Training Group | Inhibitory Control: Accuracy | Condition difference in ACC of Flanker task (post-test) | 2.60 percentage of correct response | Standard Deviation 6.12 |
| Waitlist Control Group | Inhibitory Control: Accuracy | Condition difference in ACC of Flanker task (pre-test) | 2.32 percentage of correct response | Standard Deviation 11.97 |
| Waitlist Control Group | Inhibitory Control: Accuracy | Condition difference in ACC of Flanker task (post-test) | 2.61 percentage of correct response | Standard Deviation 4.83 |
p-value: >0.05ANCOVA
Primary
Inhibitory Control: Reaction Time
Followed by the manipulation conditions, inhibitory control will be evaluated by a Flanker task (i.e., either mental fatigue condition or control condition). In the Flanker task, participants will be presented with five arrows and will be instructed to respond as quickly and accurately as possible to the direction where the middle arrow is pointing (i.e., left or right). Types of trials are the congruent (i.e., \> \> \> \> \>) and incongruent (i.e., \< \< \> \< \<). The reaction time (RT) and accuracy (ACC) of the incongruent trials were calculated as inhibitory control performance, and the difference between conditions was further calculated to represent a mental fatigue-related impairment of inhibitory control in pre-test and post-test.
Time frame: After 30-minute mental fatigue and control conditions at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Inhibitory Control: Reaction Time | Condition difference in RT of Flanker task (pre-test) | 10.79 millisecond | Standard Deviation 57.89 |
| Mindfulness Training Group | Inhibitory Control: Reaction Time | Condition difference in RT of Flanker task (post-test) | 4.11 millisecond | Standard Deviation 19.63 |
| Waitlist Control Group | Inhibitory Control: Reaction Time | Condition difference in RT of Flanker task (pre-test) | 5.47 millisecond | Standard Deviation 42.72 |
| Waitlist Control Group | Inhibitory Control: Reaction Time | Condition difference in RT of Flanker task (post-test) | -0.61 millisecond | Standard Deviation 19.9 |
p-value: >0.05ANCOVA
Secondary
Dispositional Mindfulness
The change in dispositional mindfulness was assessed using the 16-item (5-Likert scale) athlete mindfulness questionnaire (AMQ). The mean score range is between 1-5. Higher mean scores indicate a higher level of dispositional mindfulness.
Time frame: Baseline (pre-test) and 8 weeks (post-test)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Dispositional Mindfulness | AMQ score in pre-test | 3.94 score on a scale | Standard Deviation 0.59 |
| Mindfulness Training Group | Dispositional Mindfulness | AMQ score in post-test | 4.13 score on a scale | Standard Deviation 0.55 |
| Waitlist Control Group | Dispositional Mindfulness | AMQ score in post-test | 3.87 score on a scale | Standard Deviation 0.44 |
| Waitlist Control Group | Dispositional Mindfulness | AMQ score in pre-test | 4.04 score on a scale | Standard Deviation 0.53 |
p-value: <0.05ANCOVA
Secondary
Mood State: Anger
Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher anger mood.
Time frame: Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Mood State: Anger | Change of anger in pre-mental fatigue condition | 0.13 score on a scale | Standard Deviation 0.64 |
| Mindfulness Training Group | Mood State: Anger | Change of anger in post-mental fatigue condition | 0.21 score on a scale | Standard Deviation 0.52 |
| Mindfulness Training Group | Mood State: Anger | Change of anger in pre-control condition | 0.12 score on a scale | Standard Deviation 0.38 |
| Mindfulness Training Group | Mood State: Anger | Change of anger in post-control condition | -0.04 score on a scale | Standard Deviation 0.36 |
| Waitlist Control Group | Mood State: Anger | Change of anger in post-control condition | -0.03 score on a scale | Standard Deviation 0.31 |
| Waitlist Control Group | Mood State: Anger | Change of anger in pre-mental fatigue condition | 0.06 score on a scale | Standard Deviation 0.24 |
| Waitlist Control Group | Mood State: Anger | Change of anger in pre-control condition | 0.37 score on a scale | Standard Deviation 0.49 |
| Waitlist Control Group | Mood State: Anger | Change of anger in post-mental fatigue condition | 0.05 score on a scale | Standard Deviation 0.33 |
p-value: >0.05ANCOVA
Secondary
Mood State: Confusion
Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher confusion mood.
Time frame: Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Mood State: Confusion | Change of confusion in pre-mental fatigue condition | 0.59 score on a scale | Standard Deviation 0.78 |
| Mindfulness Training Group | Mood State: Confusion | Change of confusion in post-mental fatigue condition | 0.70 score on a scale | Standard Deviation 0.63 |
| Mindfulness Training Group | Mood State: Confusion | Change of confusion in pre-control condition | 0.37 score on a scale | Standard Deviation 0.49 |
| Mindfulness Training Group | Mood State: Confusion | Change of confusion in post-control condition | 0.18 score on a scale | Standard Deviation 0.4 |
| Waitlist Control Group | Mood State: Confusion | Change of confusion in post-control condition | 0.30 score on a scale | Standard Deviation 0.56 |
| Waitlist Control Group | Mood State: Confusion | Change of confusion in pre-mental fatigue condition | 0.56 score on a scale | Standard Deviation 0.75 |
| Waitlist Control Group | Mood State: Confusion | Change of confusion in pre-control condition | 0.29 score on a scale | Standard Deviation 0.54 |
| Waitlist Control Group | Mood State: Confusion | Change of confusion in post-mental fatigue condition | 0.50 score on a scale | Standard Deviation 0.56 |
p-value: >0.05ANCOVA
Secondary
Mood State: Depression
Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher depression mood.
Time frame: Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Mood State: Depression | Change of depression in pre-mental fatigue condition | 0.07 score on a scale | Standard Deviation 0.56 |
| Mindfulness Training Group | Mood State: Depression | Change of depression in pre-control condition | 0.12 score on a scale | Standard Deviation 0.38 |
| Mindfulness Training Group | Mood State: Depression | Change of depression in post-mental fatigue condition | 0.17 score on a scale | Standard Deviation 0.5 |
| Mindfulness Training Group | Mood State: Depression | Change of depression in post-control condition | -0.01 score on a scale | Standard Deviation 0.25 |
| Waitlist Control Group | Mood State: Depression | Change of depression in post-control condition | -0.07 score on a scale | Standard Deviation 0.38 |
| Waitlist Control Group | Mood State: Depression | Change of depression in post-mental fatigue condition | 0.14 score on a scale | Standard Deviation 0.52 |
| Waitlist Control Group | Mood State: Depression | Change of depression in pre-control condition | -0.01 score on a scale | Standard Deviation 0.28 |
| Waitlist Control Group | Mood State: Depression | Change of depression in pre-mental fatigue condition | 0.05 score on a scale | Standard Deviation 0.38 |
p-value: >0.05ANCOVA
Secondary
Mood State: Fatigue
Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher fatigue mood.
Time frame: Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Mood State: Fatigue | Change of fatigue in post-mental fatigue condition | 1.04 score on a scale | Standard Deviation 0.9 |
| Mindfulness Training Group | Mood State: Fatigue | Change of fatigue in pre-mental fatigue condition | 1.23 score on a scale | Standard Deviation 1.07 |
| Mindfulness Training Group | Mood State: Fatigue | Change of fatigue in pre-control condition | 0.98 score on a scale | Standard Deviation 0.93 |
| Mindfulness Training Group | Mood State: Fatigue | Change of fatigue in post-control condition | 0.65 score on a scale | Standard Deviation 0.92 |
| Waitlist Control Group | Mood State: Fatigue | Change of fatigue in post-control condition | 0.64 score on a scale | Standard Deviation 0.81 |
| Waitlist Control Group | Mood State: Fatigue | Change of fatigue in post-mental fatigue condition | 0.86 score on a scale | Standard Deviation 0.85 |
| Waitlist Control Group | Mood State: Fatigue | Change of fatigue in pre-mental fatigue condition | 1.26 score on a scale | Standard Deviation 1 |
| Waitlist Control Group | Mood State: Fatigue | Change of fatigue in pre-control condition | 0.78 score on a scale | Standard Deviation 0.94 |
p-value: >0.05ANCOVA
Secondary
Mood State: Tension
Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher tension mood.
Time frame: Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Mood State: Tension | Change of tension in post-control condition | -0.00 score on a scale | Standard Deviation 0.35 |
| Mindfulness Training Group | Mood State: Tension | Change of tension in post-mental fatigue condition | 0.20 score on a scale | Standard Deviation 0.54 |
| Mindfulness Training Group | Mood State: Tension | Change of tension in pre-mental fatigue condition | 0.06 score on a scale | Standard Deviation 0.69 |
| Mindfulness Training Group | Mood State: Tension | Change of tension in pre-control condition | 0.07 score on a scale | Standard Deviation 0.4 |
| Waitlist Control Group | Mood State: Tension | Change of tension in pre-control condition | 0.04 score on a scale | Standard Deviation 0.54 |
| Waitlist Control Group | Mood State: Tension | Change of tension in pre-mental fatigue condition | 0.14 score on a scale | Standard Deviation 0.43 |
| Waitlist Control Group | Mood State: Tension | Change of tension in post-mental fatigue condition | 0.11 score on a scale | Standard Deviation 0.42 |
| Waitlist Control Group | Mood State: Tension | Change of tension in post-control condition | -0.05 score on a scale | Standard Deviation 0.41 |
p-value: >0.05ANCOVA
Secondary
Mood State: Vigour
Mood state change was determined by the difference in scores on the Brunel Mood Scale-Chinese (BRUMS-C) between before and after manipulation. The BRUMS-C contains 23 item (5-Likert scale) and is divided into six sub-scales: anger, confusion, depression, fatigue, tension, and vigour. The mean score range is between 0-4. Higher mean scores indicate a higher vigor mood.
Time frame: Before, after 30-minute Stroop task in the mental fatigue and control condition at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Mood State: Vigour | Change of vigour in post-mental fatigue condition | -0.74 score on a scale | Standard Deviation 0.75 |
| Mindfulness Training Group | Mood State: Vigour | Change of vigour in pre-mental fatigue condition | -0.92 score on a scale | Standard Deviation 0.78 |
| Mindfulness Training Group | Mood State: Vigour | Change of vigour in pre-control condition | -0.81 score on a scale | Standard Deviation 0.78 |
| Mindfulness Training Group | Mood State: Vigour | Change of vigour in post-control condition | -0.49 score on a scale | Standard Deviation 0.71 |
| Waitlist Control Group | Mood State: Vigour | Change of vigour in post-control condition | -0.68 score on a scale | Standard Deviation 0.64 |
| Waitlist Control Group | Mood State: Vigour | Change of vigour in pre-control condition | -0.85 score on a scale | Standard Deviation 0.66 |
| Waitlist Control Group | Mood State: Vigour | Change of vigour in pre-mental fatigue condition | -1.05 score on a scale | Standard Deviation 0.92 |
| Waitlist Control Group | Mood State: Vigour | Change of vigour in post-mental fatigue condition | -0.71 score on a scale | Standard Deviation 0.72 |
p-value: >0.05ANCOVA
Secondary
Objective Mental Fatigue
Both at baseline and post-intervention, participants completed either a 30-min 100% incongruent version Stroop task (i.e., mental fatigue condition) or a 30-min 100% congruent version Stroop task (i.e., control condition). In the Stroop task, accuracy (ACC) was calculated as an index of objective mental fatigue. It is expressed as a percentage, determined by dividing the number of correct responses by the total number of responses.
Time frame: Post 30-minute mental fatigue and control condition at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 1 in post-test (mental fatigue condition) | 87.25 percentage | Standard Deviation 8.13 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 5 in pre-test (mental fatigue condition) | 82.94 percentage | Standard Deviation 16.29 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 2 in post-test (mental fatigue condition) | 84.69 percentage | Standard Deviation 9.87 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 1 in pre-test (mental fatigue condition) | 87.09 percentage | Standard Deviation 9.82 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 3 in post-test (mental fatigue condition) | 83.20 percentage | Standard Deviation 11.14 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 1 in pre-test (control condition) | 91.65 percentage | Standard Deviation 6.1 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 4 in post-test (mental fatigue condition) | 83.70 percentage | Standard Deviation 10.92 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 2 in pre-test (control condition) | 89.61 percentage | Standard Deviation 8.53 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 5 in post-test (mental fatigue condition) | 82.06 percentage | Standard Deviation 13.29 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 3 in pre-test (mental fatigue condition) | 82.54 percentage | Standard Deviation 13.8 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 1 in post-test (control condition) | 93.21 percentage | Standard Deviation 5.47 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 3 in pre-test (control condition) | 86.92 percentage | Standard Deviation 12.89 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 2 in post-test (control condition) | 90.84 percentage | Standard Deviation 7.28 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 4 in pre-test (control condition) | 87.94 percentage | Standard Deviation 8.77 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 3 in post-test (control condition) | 90.85 percentage | Standard Deviation 6.14 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 4 in pre-test (mental fatigue condition) | 83.72 percentage | Standard Deviation 13.3 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 4 in post-test (control condition) | 88.81 percentage | Standard Deviation 7.19 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 5 in pre-test (control condition) | 86.70 percentage | Standard Deviation 10.68 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 5 in post-test (control condition) | 87.41 percentage | Standard Deviation 8.48 |
| Mindfulness Training Group | Objective Mental Fatigue | The ACC of Stroop_Block 2 in pre-test (mental fatigue condition) | 83.77 percentage | Standard Deviation 1.43 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 5 in post-test (control condition) | 88.68 percentage | Standard Deviation 8.09 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 1 in pre-test (mental fatigue condition) | 88.11 percentage | Standard Deviation 8.92 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 2 in pre-test (mental fatigue condition) | 85.27 percentage | Standard Deviation 12.18 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 3 in pre-test (mental fatigue condition) | 86.36 percentage | Standard Deviation 11.12 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 4 in pre-test (mental fatigue condition) | 85.36 percentage | Standard Deviation 11.24 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 5 in pre-test (mental fatigue condition) | 82.63 percentage | Standard Deviation 17.43 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 2 in pre-test (control condition) | 91.52 percentage | Standard Deviation 5.47 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 3 in pre-test (control condition) | 90.68 percentage | Standard Deviation 7.03 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 4 in pre-test (control condition) | 88.96 percentage | Standard Deviation 9.9 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 5 in pre-test (control condition) | 85.62 percentage | Standard Deviation 11.96 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 1 in post-test (mental fatigue condition) | 87.77 percentage | Standard Deviation 10.21 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 2 in post-test (mental fatigue condition) | 85.93 percentage | Standard Deviation 9.81 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 3 in post-test (mental fatigue condition) | 84.73 percentage | Standard Deviation 11.75 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 4 in post-test (mental fatigue condition) | 84.41 percentage | Standard Deviation 10.04 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 5 in post-test (mental fatigue condition) | 84.24 percentage | Standard Deviation 10.86 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 1 in post-test (control condition) | 94.35 percentage | Standard Deviation 4.42 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 2 in post-test (control condition) | 91.59 percentage | Standard Deviation 5.93 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 3 in post-test (control condition) | 91.97 percentage | Standard Deviation 6.27 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 4 in post-test (control condition) | 90.08 percentage | Standard Deviation 5.86 |
| Waitlist Control Group | Objective Mental Fatigue | The ACC of Stroop_Block 1 in pre-test (control condition) | 92.63 percentage | Standard Deviation 5.83 |
p-value: <0.01ANOVA
Secondary
Perception of Effort
During the graded exercise test, the perception of effort will be asked at beginning and every 2.5-min using Borg 6 to 20 scale, until the participant comes to voluntary exhaustion.
Time frame: every 2.5 minutes during graded exercise test
Secondary
Subjective Mental Fatigue
Both in the baseline and post-intervention, the visual analog scale for mental fatigue (VAS-MF) was used to assess changes in subjective mental fatigue before and after experimental manipulation. The scale ranges from 0 (not at all mentally fatigued) to 100 (extremely mentally fatigued).
Time frame: Before, after 30-minute Stroop task and after Flanker task in the mental fatigue and control condition at pre-test and post-test (8 weeks)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T2 in pre-test (mental fatigue condition) | 47.69 score on a scale | Standard Deviation 13.66 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T1 in post-test (mental fatigue condition) | 22.38 score on a scale | Standard Deviation 13.43 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T1 in pre-test (control condition) | 24.81 score on a scale | Standard Deviation 13.38 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T2 in post-test (mental fatigue condition) | 48.50 score on a scale | Standard Deviation 13.79 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T1 in pre-test (mental fatigue condition) | 25.19 score on a scale | Standard Deviation 11.44 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T3 in post-test (mental fatigue condition) | 50.77 score on a scale | Standard Deviation 15.56 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T2 in pre-test (control condition) | 36.92 score on a scale | Standard Deviation 16 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T1 in post-test (control condition) | 21.08 score on a scale | Standard Deviation 12.94 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T3 in pre-test (mental fatigue condition) | 57.12 score on a scale | Standard Deviation 16.01 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T2 in post-test (control condition) | 36.69 score on a scale | Standard Deviation 13.49 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T3 in pre-test (control condition) | 40.77 score on a scale | Standard Deviation 16.89 |
| Mindfulness Training Group | Subjective Mental Fatigue | VAS score at T3 in post-test (control condition) | 35.08 score on a scale | Standard Deviation 10.62 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T3 in post-test (control condition) | 42.07 score on a scale | Standard Deviation 12.43 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T1 in pre-test (mental fatigue condition) | 24.26 score on a scale | Standard Deviation 10.89 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T2 in pre-test (mental fatigue condition) | 49.07 score on a scale | Standard Deviation 16.06 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T3 in pre-test (mental fatigue condition) | 55.56 score on a scale | Standard Deviation 22.67 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T1 in pre-test (control condition) | 21.30 score on a scale | Standard Deviation 11.4 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T2 in pre-test (control condition) | 39.26 score on a scale | Standard Deviation 11.49 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T3 in pre-test (control condition) | 40.19 score on a scale | Standard Deviation 13.9 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T1 in post-test (mental fatigue condition) | 22.78 score on a scale | Standard Deviation 11.06 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T2 in post-test (mental fatigue condition) | 50.52 score on a scale | Standard Deviation 18.09 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T3 in post-test (mental fatigue condition) | 50.78 score on a scale | Standard Deviation 18.27 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T1 in post-test (control condition) | 24.04 score on a scale | Standard Deviation 15.63 |
| Waitlist Control Group | Subjective Mental Fatigue | VAS score at T2 in post-test (control condition) | 42.04 score on a scale | Standard Deviation 14.27 |
p-value: <0.01ANOVA