I want to study in the industrial environment about increasing physical activity and improving healthy nutrition and need guidance for the most effective strategy.
You may find this book informative (e-book is available for download) "Glanz, Karen, Barbara K. Rimer, and Kasisomayajula Viswanath, eds. Health behavior and health education: theory, research, and practice. John Wiley & Sons, 2008."
May find this review also informative "Conn, Vicki S., Adam R. Hafdahl, and David R. Mehr. "Interventions to increase physical activity among healthy adults: meta-analysis of outcomes." American journal of public health 101, no. 4 (2011): 751-758."
Morgan GS, Haase AM, Campbell R, Ben-Shlomo Y. Physical ACtivity facilitation for Elders (PACE): study protocol for a randomised controlled trial. Trials. 2015;16:91. Published 2015 Mar 13. doi:10.1186/s13063-015-0610-8