Table 1.

Treatment and cognitive task descriptions that participants read.

Intervention	Description provided to participants
Supervised bicycle ergometer training session at moderate intensity	Imagine you would participate in the following treatment as part of the trial: Initially you do a warm up on the bicycle ergometer on a very low intensity for 2–3 min. Following this, the investigator raises the resistance of the bicycle until you reach a heart rate of 65–70% of your individual maximum heart rate. Most young, healthy adults perceive this intensity as slightly demanding to demanding. You maintain this intensity on the bicycle ergometer for 25 min. If your heart rate increases above, or decreases below 65–70% of your maximum heart rate, the investigator adapts the resistance of the ergometer in the intention to return you to the defined intensity. After completion of the 25 min of load you do a cool down of 2–3 min on a very low intensity level.
Supervised bicycle ergometer training session at vigorous intensity	Imagine you would participate in the following treatment as part of the trial: Initially you do a warm up on the bicycle ergometer on a very low intensity for 2–3 min. Following this, the investigator raises the resistance of the bicycle until you reach a heart rate of 85–90% of your individual maximum heart rate. Most young, healthy adults perceive this intensity as exhausting. You maintain this intensity on the bicycle ergometer for 25 min. If your heart rate increases above, or decreases below 85–90% of your maximum heart rate, the investigator adapts the resistance of the ergometer in the intention to return you to the defined intensity. After completion of the 25 min of load you do a cool down of 2–3 min on a very low intensity level.
Sitting alone in a room waiting	Imagine you would participate in the following treatment as part of the trial: You calmly sit in a waiting room without distraction for approximately 30 min.
Sitting alone in a room reading	Imagine you would participate in the following treatment as part of the trial: You sit in a waiting room for approximately 30 min, reading a book about endurance training and its physiological effects.
Sitting alone in a room watching an exercise related video	Imagine you would participate in the following treatment as part of the trial: You sit in a waiting room for approximately 30 min, watching a video about endurance training and its physiological effects.
Supervised bicycle ergometer training session at low intensity	Imagine you would participate in the following treatment as part of the trial: Initially you do a warm up on the bicycle ergometer on a very low intensity for 2–3 min. Following this, the investigator raises the resistance of the bicycle until you reach a heart rate of 45–50% of your individual maximum heart rate. Most young, healthy adults perceive this intensity as easy. You maintain this intensity on the bicycle ergometer for 25 min. If your heart rate increases above, or decreases below 45–50% of your maximum heart rate, the investigator adapts the resistance of the ergometer in the intention to return you to the defined intensity. After completion of the 25 min of load you do a cool down of 2–3 min on a very low intensity level.
Supervised stretching, myofascial release and coordination training session	Imagine you would participate in the following treatment as part of the trial: You do three sections of physical activity with respectively three exercises. The first section is composed of 3 coordination and balance exercises. The second section is composed of 3 exercises of a myofascial training with the aid of a foam roll. The third section is composed of 3 stretching exercises. Every exercise is shown by the investigator at first and is accomplished for 20–30 s on each side by yourself. Between the exercises you rest for a few seconds. You pass all of the nine exercises successively supervised by the investigator. Following this, you repeat all nine exercises a second time, without supervision. Most young, healthy adults perceive this intensity as easy. The treatment lasts approximately 30 min.
Supervised myofascial release training session	Imagine you would participate in the following treatment as part of the trial: You pass seven exercises of a myofascial training with the aid of a foam roll. Every exercise is shown by the investigator at first and is then accomplished for 20–30 min on each side by yourself. Between the exercises you rest for 60 s. You pass all of the seven exercises successively supervised by the investigator. Following this, you repeat all seven exercises a second time without supervision. Most young healthy adults perceive this intensity as easy. The treatment lasts approximately 30 min.
Stroop-task	Words that express one of four colors (red, blue, green, yellow) are shown successively to you on a screen, but are written in a deviant color (red, blue, green, yellow). Your task is to choose the color, in which the word is written as fast and correct as possible on a keyboard. There is one practice run before the test starts. The test lasts 3–4 min and measures your response time and your count of errors.
Trail Making Test–part B	The numbers 1–13 and letters A–L are shown randomly ordered to you on a screen. Your task is to connect the numbers and letters alternately in an ascending order by point-and-click as fast and correct as possible. There is one practice run, before the test starts. The test lasts 1 min and measures the time you need to connect the numbers and letters.
Free-recall task	At first 40 nouns are shown successively to you on a screen. Your task is to memorize as many words as possible. When all 40 words were shown, you should rest for 60 s and afterwards reproduce the words you can remember. The test lasts ca. 6 min and counts the correctly recalled nouns.