For a six-day split routine, where each day focuses on a different muscle group, the following is a common breakdown of muscle groups and the associated days (as commonly observed in the lifting community): See the note on cardio at the bottom... Monday: Chest This day is dedicated to exercises that primarily target the chest muscles, such as bench press, chest flyes, and push-ups. Tuesday: Back On this day, the focus is on exercises that engage the back muscles, including lat pulldowns, rows (barbell, dumbbell, or machine variations), and pull-ups. Wednesday: Legs Wednesday is typically dedicated to leg workouts, targeting the quadriceps, hamstrings, glutes, and calves. Exercises may include squats, lunges, leg presses, leg extensions, and leg curls. Thursday: Shoulders This day is focused on exercises that primarily target the shoulder muscles, such as shoulder presses, lateral raises, front raises, and upright rows. Friday: Arms (Biceps and Triceps) On this day, exercises are specifically chosen to work the biceps and triceps. Examples include bicep curls, hammer curls, tricep pushdowns, tricep dips, and skull crushers. Saturday: Core and Abs This day typically involves exercises that target the core muscles, including the abdominals, obliques, and lower back. Planks, crunches, Russian twists, and leg raises are common exercises for this day. Sunday is usually designated as a rest day to allow for recovery and to prevent overtraining. What About Cardio???: Every day! Keep your heart rate at target rate as you exercise for 30 to 90 minutes and you will get an outstanding cardiovascular workout! BUT...The best option is to HIIT it by running uphill hard till you can't breathe then walking downhill until you catch your breath then running uphill again! Do that for 15 to 20 minutes on your lazy Sunday for a perfect round-off for your week. Cheers!