What is the recommended Daily Deliberate Practice Limit?

In her book Grit, the author Angela has touched upon a very interesting metric of the daily deliberate practice limit.

This metric has been derived after studying the behavior patterns of all world experts and their deliberate practice regime.

After studying all such patterns the limit for such rigorous practice has been capped between three to five hours per day at a maximum.

The below insight inspired from the same book elaborates on this interesting metric.

For another such interesting insight from the same book, please visit the following link:

https://viewpointsunplugged.com/four-psychological-assets-of-grit/

To know more about Deliberate Practice please visit the below link:

https://sentio.org/what-is-deliberate-practice