What do Constitutional law scholars mean when they refer to the "Lochner era" and how is it connected to the doctrine of substantive due process? Please discuss at least three cases across at least three different weeks on the syllabus as evidence to support your answer.

Please use these cases:

Adair v. United States: https://www.oyez.org/cases/1900-1940/208us161

Adkins v. Childrens Hospital: https://www.oyez.org/cases/1900-1940/261us525

Muller v. Oregon: https://www.oyez.org/cases/1900-1940/208us412