In what order should you complete your exercises during your training? That depends on what your goal is: (mainly) muscle growth or (mainly) muscle strength.
STRENGTH VERSUS MUSCLE GROWTH
In a meta-analysis by Nunes et al., no effect of exercise order on muscle growth was found. The weekly training volume is what counts for muscle growth.
If you mainly train for strength, there will be little effect if you start your sessions with the exercises in which you want to become stronger. And that makes sense: the heavier you can go, the more strength you will gain. If desired, start your training with the exercise in which you are weakest.
ORDER OF HYPERTROPHY TRAINING
Does the order of exercises really have no effect on muscle growth (hypertrophy)? Maybe, a little, as a study by Brandão et al. suggests.
If you apply the following rules, you will always be fine:
- Start your training with compound exercises (for example squats before leg extensions)*;
- Start with the muscle groups that you find most important;
- Do you train almost every day? Then make sure that each muscle group is trained at first once a week;
- Organize your training in such a way that you save time (for example from dumbbell to dumbbell exercise, or doing supersets);
- Do abdominal exercises at the end of your training;
- Do any cardio after strength training.
* In some situations you consciously do an isolation exercise before a compound exercise, for example cable flyes before bench presses, in order to optimally isolate the chest.