Final answer:
Textbooks recommend using electrocardiograms (ECG/EKG) and echocardiograms (ECHO) to evaluate periods of the cardiac cycle, although ballistocardiographs (BCG) have also been used historically.
Step-by-step explanation:
To evaluate certain periods of the cardiac cycle, textbooks often recommend using tools such as the electrocardiogram (ECG or EKG) and echocardiogram (cardiac ECHO or ECHO).
The cardiac cycle includes periods of atrial systole, ventricular systole, atrial diastole, and ventricular diastole.
The ballistocardiograph (BCG) was also a tool used historically to measure the strength of the heart using the principles of Newton's third law, by detecting the recoil of the body due to the heartbeat.
However, it has been largely replaced by the ECG and ECHO for assessing the cardiac cycle and the heart's function.