Physiological changes in threshold.
D000328:Adult; D000368:Aged; D004558:Electric Stimulation; D005260:Female; D005947:Glucose / Q000378:metabolism; D006321:Heart / Q000502:physiology*; D006327:Heart Block / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D010138:Pacemaker, Artificial; D005082:Physical Exertion; D011187:Posture; D011188:Potassium / Q000378:metabolism
D005947:Glucose; D011188:Potassium