There are 3 main types of grip widths commonly used in the bench press. Close (shoulder width), mid-grip, and a wide-grip (think powerlifting width). Your goal will generally determine the amount of time you spend training each variation. Personally I train with a close grip for the majority of my phases, using a mid-grip secondly as a variation, and then rarely a wide grip. This is because the close grip puts less stress on the shoulder joint then the other two widths and with my history of shoulder and pec injuries it is the grip that allows me to train pain free. I also program this width in a lot for my athletes as I feel it carries over to their sports a lot more than a wide grip does and it also reduces the chance of injuring the shoulder during training.
Using a close grip also recruits more triceps than the wide grip bench press and you use a longer range of motion. So even if you are a powerlifter or someone who just wants to bench the biggest amount possible, incorporating some close grip bench presses in the early phases of your training cycle can be a good idea. I know Ed Coan programmed them into his cycles and he spoke of their benefits during a seminar I attended with him in 2014, his results speak for themselves so I think it is good advice. Ed typically did his competitive bench press first, followed by some paused close grip benches, and then finished off with some paused incline presses.
Another thing to consider is where you are getting stuck on the lift. If you are getting pinned in the bottom position then incorporating some wide grip benches may help. The thing is you have to be careful to not go crazy on these lifts as the risk of a pec tear is greatly increased in my opinion. Go lighter and do 5 or more reps as a minimum to reduce the risk. If you have had shoulder injuries in the past then I would stay away from super wide benches and use other techniques to increase strength off the chest such as dumbbell work, dead stops, and other methods where you can use a safer grip width but still work on your weakness.
If you are struggling with locking out then the close grip bench is a good width to use as it makes the lift harder from mid-range until lockout. Incorporating things like board press, floor presses, dead stops from the rack at your sticking point, and rack lock outs might also help. Most of the time generating more speed off the chest is enough for raw lifters to help them accelerate through the sticking point.
For the general population sticking to a close grip is the best bet as it reduces the chance of injury. Most of the time their goal is to just look good anyway and they don’t really care how much they can bench. As mentioned above this grip is healthiest for the shoulders and you can use different angles as variations. By doing this clients will reduce their risk of an overuse injury, get stronger through different ranges of motion and at different angles which will carry over to daily activities, and also avoid boredom.
When it comes to grip width I feel the most important thing is to know your goal. If you are a competitive powerlifter who has to lift the most weight possible then you will more than likely use a wider grip. Depending on anatomical structure, past injuries etc. this grip will vary from athlete to athlete. Other grips and angles such as close, mid, and reverse grip would be used as accessory or assistance lifts. For the competitive athletes that use strength training to aid in the performance of their chosen sport, the demands of that sport and the carry-over from the weight room to the athletic arena will determine the amount of time spent using each type of width and angle of bench used. As an example, (something I again learnt from Charles Poliquin), is that in judo the greatest carry-over comes from using the close grip incline bench press as this angle and grip width more closely replicates the position they are in when trying to keep an opponent away. If this lift improves in the gym then generally performance on the mat improves.
Keeping athletes healthy is also the priority, not lifting maximal weights at all costs, so this will also determine grip width chosen. You may sacrifice some weight on the bar but it doesn’t matter for athletes, you can still get them strong using a closer grip and you will keep them healthy so they are ready to compete in their sport. Variety is the key but how much time you spend using each grip width will differ.
Here is a good article that talks about the difference between geared lifting and raw lifting and why it is important to find your own grip:
Bench Press Tip - Elbow Position
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