Outcome
Type |
Measure |
Description |
Time frame |
Safety issue |
Primary |
Knee flexion angle at the midstance while running. |
Assessment of the knee flexion angle (in degrees). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Ankle dorsiflexion angle at the midstance while running. |
Assessment of the ankle dorsiflexion angle (in degrees). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Step rate while running. |
Assessment of the step rate (in steps/minute). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Contact time while running. |
Assessment of the time the foot is in contact with the ground (in seconds). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Stride length while running. |
Assessment of the distance between two successive placements of the same foot (in meters). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Flight time while running. |
Assessment of the time the foot is not in contact with the ground (in seconds). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Running performance modification. |
Assessment of the time (in seconds) required to complete a specific distance running on a treadmill. The measurement will be done before and after a fatiguing protocol. Assessed using a stopwatch. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Hip angle while squatting, at the initial position, bottom position, and final position, and the eccentric and the concentric range of movement. |
Assessment of the hip angle (in degrees). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Knee angle while squatting, at the initial position, bottom position, and final position, and the eccentric and the concentric range of movement. |
Assessment of the knee angle (in degrees). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Ankle angle while squatting, at the initial position, bottom position, and final position, and the eccentric and the concentric range of movement. |
Assessment of the ankle angle (in degrees). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Execution time while squatting, for the eccentric and the concentric phases of the movement. |
Assessment of the execution time to perform the eccentric and the concentric phases of the squat (in seconds). The measurement will be done before and after a fatiguing protocol. Assessed using a linear position transducer. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Peak vertical force while squatting, for the eccentric and the concentric phases of the movement. |
Assessment of the peak vertical force (in Newtons). The measurement will be done before and after a fatiguing protocol. Assessed using a linear position transducer. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Rate of force development while squatting, for the eccentric and the concentric phases of the movement. |
Assessment of the rate of force development (in Newtons/seconds). The measurement will be done before and after a fatiguing protocol. Assessed using a linear position transducer. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Squatting performance modification. |
Assessment of the mean propulsive bar velocity (in meters/seconds) for a specific weight lifted in barbell back squats. The measurement will be done before and after a fatiguing protocol. Assessed using a linear position transducer. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Contralateral pelvic drop angle while jumping, at the initial contact of the landing phase. |
Assessment of the contralateral pelvic drop angle (in degrees). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Knee valgus while jumping, at the initial contact and the deepest landing position of the landing phase, and the range of movement between these two moments. |
Assessment of the knee valgus angle (in degrees). The measurement will be done before and after a fatiguing protocol. Assessed using kinematic instruments. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Unweighting phase duration while jumping (jumping phase). |
Assessment of the unweighting phase duration (in seconds). The measurement will be done before and after a fatiguing protocol. Assessed using force plates. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Braking phase duration while jumping (jumping phase). |
Assessment of the braking phase duration (in seconds). The measurement will be done before and after a fatiguing protocol. Assessed using force plates. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Propulsive phase duration while jumping (jumping phase). |
Assessment of the propulsive phase duration (in seconds). The measurement will be done before and after a fatiguing protocol. Assessed using force plates. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Relative peak power output while jumping (jumping phase). |
Assessment of the relative peak power output (in Watts/kg). The measurement will be done before and after a fatiguing protocol. Assessed using force plates. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Primary |
Jumping performance modification. |
Assessment of the height (in meters) of countermovement jumps. The measurement will be done before and after a fatiguing protocol. Assessed using force plates. |
During the control, placebo, and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Secondary |
Supplementation identification. |
Assessment of the participants' perception regarding the ingested substance. They will have to complete a questionnaire immediately before (1 hour post-supplementation) and after the assessed exercises, indicating what substance they believe that they have consumed, with the options "caffeine", "placebo", or "I don't know", as well as the reason why they have chosen that answer. |
During the placebo and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
|
Secondary |
Side effects. |
Assessment of the participant's side effects related to caffeine consumption. In the morning of the day after the sessions, they will be requested to complete a questionnaire comprised of 8 questions with a yes/no answer, to evaluate the side effects of caffeine consumption during the hours after the sessions. |
During the day after the placebo and caffeine sessions (at least 7 days between them). The length of each session will be approximately 3 hours. |
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