Knee Wraps May Lead to Knee Injury
Knee Wraps when Squatting Come with a Cost
According to this article, newly published research has found that wearing knee wraps when squatting can be bad for your knees.
The concluding comment from the research is that "knee wraps should not be worn during the strength and condition [sic] process." The implied recommendation is that in a competition type of event, knee wraps may still be worth using in such a short term setting. The negative effects are more likely to show up with extended and regular use of the straps. With that said, it is probably best not to use straps even on a sporadic basis just for beating personal records and the like.
The article has more details on the study, but this summarizes the gist of it. I would like to point out the biggest strength of the study - the subjects. These were trained individuals, which is difficult to come by. They are all experienced weight lifters and were tested at an adequate strength level to participate. This means the study should be applicable to other people that are serious weight lifters.
The main source of hesitation for me looking at this study is the amount of subjects. There were only ten. Better human studies will have 30 or more subjects for testing. Likewise, probably due to budget constraints, they only tested three reps for each participant with and without the knee wraps. Ideally, they could do more reps and do it on more instances, such as checking in on the next week's squat day.
Do you use knee wraps for squatting?
Wear Them or Not?
I say it is not worth it. If you are training for appearance and health-based goals, you should not be fretting this much about strength anyway. Strength-based goals are excellent to keep you motivated on a day to day basis, but you would be better served to change your program, deload, or something like that instead of using wraps to up your max. The knee wraps will alter your musculature according to that study, so you should try to build up your lower body in a way that reflects the way the body is meant to move.
Even if you are interested in strength-oriented training, you may find yourself without a working pair of knees. You will certainly need them in a competition, but the more they are used during training the more times you are putting your knees at risk. I assume this would also apply to training suits, but we cannot be sure. Please be smart and put the health of your joints over short term goals.
Try Knee Sleeves Instead
With that said, you might get the feeling you're going for with a compression sleeve with your knees. These don't give you the artificial spring that knee wraps do, but can keep the area warm and loose for your lifts. You will feel like you have the spring, but it is actually very small with a sleeve. Your performance may still go up due to your knee joints staying loose. You will probably have to shop online to find things like this since it is a such a specialty item. They are often sold at the same places that would sell you knee wraps.
I have attached a review from a lifting and fitness expert where he discusses his favorite knee sleeves and describes how they work for him and his trainees. He says that many strongman competitors even use these in their training.