1 heavy set done 1-3x/week. (81% of strength gains can be achieved with 1-4 sets per week)
Just 30-60 minutes of lifting per week is enough for maximum risk reduction (all cause mortality)
Optimal Target: 10 sets per body part per week. Split across at least 2 workouts per body part.
1-4 sets per body part per week will yield 64% of the maximum muscle gains.
5-9 sets per body part per week will yield 84% of the maximum muscle gains.
Tips for a minimalist workout
Push yourself harder. The lower your volume, the higher your intensity should be. (RPE 9-10)
Utilize drop sets. After hitting failure, drop weight by 25-50% and go to failure again.
Use sensible supersets (different muscles) for more efficient workouts.
Cut down on warmup time.
References: Jeff Nippard YT video with links to scientific studies. https://youtu.be/xc4OtzAnVMI