All solid advice above. Everyone is a bit different when it comes to insulin sensitivity - some people can eat simple sugars and carbs all day, and others are more sensitive to carbs. My protocol for a lean bulk is to consume 65-75% of your carbs around your training, an hour pre workout and with as a post workout meal. I've found this to be the best way for me to approach bulking while staying lean.
The most ideal time to spike insulin and consume simple carbs and low fat is post workout. After training, your muscles are depleted of nutrients, and spiking insulin can help deliver amino acids and nutrients into the muscle cells to speed recovery.
Consuming simple sugars and increasing insulin levels before training isn't necessary. I would recommend a complex carb, protein, and a small amount of healthy fats about an hour before training. If your goal is to optimize nutrient partitioning, I would also recommend using a GDA product like Slinmax before your preworkout meal. A GDA product can help maximize nutrient uptake to muscle cells and it can also improve cell hydration, pumps, and endurance during training.