Endless unsupported debates on what is the best footwear for the squat seem to be seasonal: they are nauseatingly long and frequent, with "debaters" commenting on the most recent weightlifting shoe brand, promising impeccable squats with X or Y shoe. Folks spend a fortune on them. The funniest part is when someone follows said unsupported advice and, sadly, sees no improvement in their performance.
That's because IF it affects strength and power outputs (which was never detected), it is an indirect result of biomechanical effects. For example: for novice trainers, elevated heels (WL shoes) decrease the moments around L4/L5 compared to level conditions (either barefoot or flat shoes). That means it is probably going to be safer and cause less lower-back problems (which shouldn't be a concern for novice lifters anyway).
Wearing WL shoes seems to reduce trunk forward-leaning, which is somewhat of a problem for short torso lifters. The more vertical torso during the squat is believed to reduce the amount of shear stress in the lower back area. The more vertical torso also affects foot segment angle and possibly contributes to greater muscle excitation in knee extensors.
But here is the problem: uncritically borrowing information from weightlifting never worked well. The WL shoe is important on WL because it reduces horizontal displacement during the snatch and the clean & jerk. That, my dear reader, makes a hell of a difference in WEIGHTLIFTING performance.
For weightlifters, WL shoes do make a lot of difference. Why else would you observe 100% of world-class competitors using them? I promise you: it's not fashion or superstition. It's performance.
Years ago, when I had already won a couple of powerlifting federation world titles and records, an all-time record and was ranked first on my weight class (all federations included), I visited a WL friend and enjoyed a training session with him, under the supervision of the national team coach. He watched silently and gave his verdict:
- you could be world-class if you had the right shoes.
I have a pair of good WL shoes because I practice WL. It may help with your squat, especially if you have ankle mobility restrictions. It won't make a champion out of you.
As for barefoot lifting, I always recommend some for proprioceptive reasons. Most people have to wear shoes at the gym. That makes it hard to recommend barefoot lifting. Anecdotal evidence shows that it improves stability secondary to improving proprioception.
That raises several other questions: do foot movement drills improve proprioception, stability, and performance? If so, which drills? If it improves performance, where does it improve it and how?
We don't know.
Bottom line is that if you just want to know what to wear for squatting and deadlifting, take a look at some of the best athletes. Most wore just chucks. If you are a weightlifter, eventually you will find that perfect beloved shoe to grow old with.