Practice IB Sports, exercise and health science (SEHS) Topic A.1.1 Inter-system Communication with authentic exam-style questions for both SL and HL students. This question bank focuses on the exact syllabus content for A.1.1 Inter-system Communication and mirrors Paper 1A, 1B, 2 style where relevant.
Get instant solutions, detailed explanations, and build confidence with questions aligned to IB examiner expectations.
Researchers conducted a longitudinal analysis of female endurance athletes across a full menstrual cycle. Hormone levels (Figure) and training-related physiological variables (Table) were measured. The aim was to explore how reproductive hormone fluctuations influence thermoregulation, fuel metabolism, and recovery, and how coaches could adapt training accordingly.
Table: Physiological Indicators During the Menstrual Cycle (Athletic Cohort Study)
| Day of Cycle | Core Temperature (°C) | Sleep Quality Score (1–10) | Muscle Glycogen Use During Exercise (g/hr) |
|---|---|---|---|
| 7 | 36.5 | 8.5 | 55 |
| 13 | 36.6 | 8.8 | 50 |
| 16 | 37.1 | 6.0 | 38 |
| 21 | 37.2 | 5.5 | 36 |
| 28 | 36.6 | 7.0 | 48 |
Figure 1: Hormonal Fluctuations Across the Menstrual Cycle
Identify the day with the highest core temperature from the table.
Using the figure, state the hormone most likely responsible for this thermogenic effect and explain its functional significance for thermoregulation.
Suggest how this thermogenic effect may influence endurance training or hydration strategies during the luteal phase.
Describe the relationship between progesterone levels and sleep quality over the second half of the cycle.
Outline one possible impact of reduced sleep quality on training recovery or performance adaptation in this cohort.
Using data from the table and figure, explain how oestradiol levels might contribute to glycogen sparing during the follicular phase.
From a coaching perspective, state which phase (follicular or luteal) may be better suited for glycogen-depleting sessions. Support your answer with specific data.
Evaluate how integrating hormonal and physiological data can be used in individualized training programs for female athletes.
During a marathon, an athlete’s pituitary gland releases antidiuretic hormone (ADH) to signal the kidneys to increase water reabsorption. Identify the two body systems interacting to maintain this homeostatic balance.
Which statement best explains why the endocrine system is more important than the nervous system for maintaining homeostasis during a marathon?
An athlete's heart rate is recorded at rest, during a period of exercise, and during recovery. The figure shows the heart rate trace.
Figure: Heart rate before, during and after exercise
Using the figure, state the athlete's heart rate at rest.
Using the figure, describe how the athlete's heart rate changes at the start of exercise.
Explain which division of the autonomic nervous system is mainly responsible for the rise in heart rate during exercise.
Explain how heart rate is returned towards its resting value during recovery.
State the type of receptor that detects changes in blood pressure.
The endocrine system regulates blood glucose concentration. The figure shows the blood glucose concentration of a healthy person after eating a meal.
Using the figure, state the set-point blood glucose concentration shown by the dashed line.
Using the figure, describe what happens to blood glucose in the first hour after the meal.
Explain the role of insulin in returning blood glucose to normal after the meal.
State the hormone that raises blood glucose when it falls too low.
Outline why maintaining blood glucose is important during prolonged exercise.