Bar push-up = barbell bench press?

Bar push-ups with an outdoor setup

I've been doing a lot of bar push-ups lately. Standard, decline, high decline, incline, with narrow grip, with shoulder width grip etc.

Here are few reasons to add it to your routine:

• Easier on the wrists. You can keep your wrists straight. 
• Tactile feedback from the bar ensures proper depth on each repetition.
• Forearms can be perpendicular to the ground. On the standard pushup the elbows are pointing slightly backwards unless your wrists form a 90 degree angle which is not anatomically possible for almost anyone.
• You can lift the bar high enough to do full range of motion decline push-ups without your head getting in the way. I like to touch the upper chest with the bar when doing the decline push-up. Just like with the barbell incline bench press.
• For me it just feels more stable and I'm able to train hard.
• Mimics the barbell bench press quite well. My numbers on the barbell bench press and bar push-up seem to be quite close to each other.
• Still has a freely moving scapula instead of a fixed position compared to bench press.

If you are worried that the bar is elevated too high making the exercise easier and turning it into an incline push-up you can elevate your feet also to match the level of the bar. It makes a slight difference in the resistance at the bottom of the push-up. 

Alternative setup for weighted decline push-ups. With this level of elevation I can do full range of motion decline bar push-ups without hitting my face to the ground on each rep

This is best done with a fixed or supported bar or barbell. Meaning that the bar should not move. The standard barbell pushup without any support is a different exercise since you have to fight against the barbell slipping forward or backwards. You want to lock the bar in place so that it does not slip for maximum stability. Of course you can use regular push-up handles that are properly aligned but then you will lose the tactile feedback of the bar. I like to touch the bar below my chest to indicate the proper bar path. With the push-up handles you might go too high or too low or too deep or too shallow. In that case you could use a strap between push-up handles to align them correctly and get touch feedback.

Alternative setups. Narrow hammer grip with push-up handles and standard grip with an elevated broomstick.

Like the knuckle push-up this variation feels more right for my body. The standard pushup can slightly bother my shoulders from time to time but the bar aligns my joints to a better angle. So give this push-up a try and see how it feels. I've been using a basic broomstick also for this exercise as long as you support the stick properly so that it does not break. This makes the exercise accessible to almost anyone. Just use a broomstick and some books to lift the bar off the ground.