What is "preload"

n. The end diastolic pressure that stretches the right or left ventricle of the heart to its greatest geometric dimensions under variable physiologic demand. vb. 1 (context transitive English) To load in advance (used especially in reference to software installed on a computer prior to sale). 2 (context intransitive British slang English) To drink cheap alcohol at home before going out socially.

In cardiac physiology, preload is the end diastolic volume that stretches the right or left ventricle of the heart to its greatest dimensions under variable physiologic demand. In other words, it is the initial stretching of the cardiomyocytes prior to contraction; therefore, it is related to the sarcomere length at the end of diastole. Parameters such as ventricular end diastolic volume or pressure are used to measure preload since the ideal length of the cardiac sarcomere cannot be measured. Passive filling of the (heart) ventricle and subsequent atrial contraction thus allows an echocardiographically volumetric measurement. Preload is theoretically most accurately described as the initial stretching of a single cardiomyocyte prior to contraction. This cannot be measured in vivo and therefore other measurements are used as estimates. Estimation may be inaccurate, for example in a chronically dilated ventricle new sarcomeres may have formed in the heart muscle allowing the relaxed ventricle to appear enlarged. The term end-diastolic volume is better suited to the clinic, although not exactly equivalent to the strict definition of preload. Atrial pressure is a surrogate for preload.

preload is a free Linux program which runs as a daemon to record statistics about usage of files by more frequently-used programs. This information is then used to keep these files preloaded into memory. This results in faster application startup times as less data needs to be fetched from disk. preload is often paired with prelink. preload was written by Behdad Esfahbod and uses Markov chains in its implementation;

Preload may refer to:

• Preload (cardiology), a term used in cardiology (the study of the heart)
• preload (software), a free software code-prefetching program for Linux
• Preload (engineering), a term used in mechanical engineering to describe the load applied to a fastener merely as a result of being fastened (and before any external loads are applied)
• The British term for pregaming, drinking alcohol at home before going to public places to drink

Preload is a mechanical engineering term with several meanings. In the general sense, it refers to the internal application of stress to certain mechanical systems.