Will long term endurance exercise really keep a youthful heart

 Willl longtime endurance exercise really preserve ( help preserve) a compliant left ventricle (LV) and mitigate the age related stiffening of the LV and the aorta?

Is the only solid evidence for that thesis the extensive work of Dr. Ben Levine and his coworkers at the Institute for Exercise and the Environment?

Some longitudinal studies have shown that active exercise achieve grater preservation of 02 max than do sedentary people but there are  studies that contradict those findings.

Possible mechanisms by which long term exercise might preserve a compliant LV include:

animal work showing that rats with long time exercise develop elongated muscle fibers

improvement in calcium transport during relaxation 'increase in myocytes and improve fatty acid oxidation decreasing lipotoxicity  Bhella , Impact of lifelong exercise dose on left ventricular compliance and distensibiity J Am Coll Cardio. 2014 vol 64 no 12 

Beware- CHATGPT 's references sometimes are fabrications

In recent weeks there have been numerous internet compliants about ChatGPT.Some of them are regarding erroneous references or citations, I had an expereince with that. I was chatting with this system about a medical case of peripheral neuropathy.It said that distance running was a recognized casue of periphral neuropathy.I asked for references and three were provided. I tried to find the references on PUbMED and they were not found.I asked for three more references.Same result.I then asked ChatGPT if the refereces were made up. It replied that It was sorry for "misunderstanding my question" The six references given were all bogus.They had title and journal names that seemed real but the actual reference was bogus. Several people have made comments on various internet sites that the references or citations provided in a ChatGPT essay were fictitious.This behavior had been referred to a "hallucinations" More recently I questioned ChatGPT about certain aspects of conduction system cardiac pacing.The discussion seemed reasonalbe as least to the level of my non EP level of knowledge but one of the references could not be confired.I asked for another referece and this time the reference was correct-that is it was a real reference but not quite what I had asked far. So if it is the case that sometimes the references are valid and sometimes not may be even worse that if they were all fabrications.At least so far it did not try to lock me out of the space ship.