Final answer:
Consuming a 20 oz. cup of coffee before exercise can increase heart rate and blood pressure, potentially improving athletic performance by reducing perceived exertion and enhancing endurance. However, it's essential to monitor for negative symptoms, especially if one is sensitive to caffeine.
Step-by-step explanation:
If your client drank a 20 oz. cup of coffee 20 minutes prior to her exercise session, it could potentially affect her heart rate (HR) and blood pressure (BP). Caffeine is known to be a stimulant that can increase HR and BP, providing a temporary boost in energy levels and possibly improving athletic performance.
Caffeine ingestion prior to aerobic exercise is associated with increased fat oxidation and a reduced perception of exertion, which might allow your client to work out more intensely or for a longer duration. However, if your client is not accustomed to caffeine or if the dose was high, it could lead to negative symptoms such as agitation, irregular heartbeat, or increased cardiovascular stress.
According to research, moderate doses of caffeine can improve athletic performance in both aerobic and anaerobic conditions by delaying the onset of muscle fatigue, enhancing muscular strength, power, endurance, and possibly increasing the basal metabolic rate. Therefore, the coffee your client consumed could enhance her workout, albeit it's important to monitor for any adverse signs due to the caffeine intake.