A growing number of people today have the opportunity, or perhaps the misfortune, of living a completely sedentary lifestyle with omnipresent access to calorically dense ultra-processed foods. Not surprisingly, global obesity and metabolic dysregulation conditions are the highest ever recorded, and continue to rise in many areas of the world. Physical activity levels are low, sedentary behavior (and especially screen time) levels are high and increasing, and global fitness levels are declining. Global megatrends including the automation, mechanization and digitization of daily routines in recent generations has resulted in a reduction in all domains of physical activity and a disruption of movement behaviours more generally. Macro-environmental forces related to systemic and structural inequities, urbanization, climate change, and commercial determinants of health serve as both magnets and facilitators for such lifestyle decay. Strategies to successfully manage these forces and changes to lifestyle behaviours have proven elusive and would benefit from a deeper understanding of foundational temporal changes to these behaviours. One method to seek this understanding is to look back in time before such megatrends existed to seek clues on how such forces can be confronted or counter-balanced. This presentation will draw on evidence from various models of going back in time to extract lessons learned from long-lost lifestyles. Embracing an appreciation for a back to the basics orientation and simplicity of apparatus approach, we are reminded to see the forest not just the tree(s). Cross-cultural comparisons (e.g., Old Order Amish, rural Kenya), natural experiments (e.g., COVID-19), holistic approaches (e.g., 24-hour movement paradigm), and historically rooted behaviours (e.g., active outdoor play) will serve as research models for this journey exploring how to move forward by looking back. Bring your DeLorean and flux-capacitor because we are going back to the future!