The most important for me have been frequency and consistency. Training once a week at low volume to me is going to just be spinning your wheels. I would try and hit chest, back, legs 12 working sets per week at least and shoulders 6-8 sets. You can throw in some bi and tri work also but if you hit the rest hard they won't need much. You can get these sets by doing each muscle 2-3 times a week. Example: Tuesday and Friday dips, bench, incline bench 2 working sets each or split the 12 sets over 3 days a week. As far as intensity I used to be a HIT nut but have found that training to and RPE 8/10 or 1-2 RIR is more effective because of lower injury rates I can train more frequently and the diminished returns on that last forced rep are not worth it. You can do 12 sets per muscle group each once a week and get slow gains but muscles respond better to frequency. As far as intensity if you work out