At the university I teach at and did my undergrad and graduate work in sports medicine/athletic training, the philosophy varied from ATC to ATC on whether you should tape all players ankles.
I personally believe that taping the ankle or wearing a brace, as stated in an earlier post, should be used with athletes with a history of ankle injuries. It can help prevent ankle injuries as well as lessen the severity of ankle sprains. Athletes who do not have a history of ankle sprains have a choice whether the get their ankles taped or not, but after the first ankle injury, they are taped or braced for the rest of the season.
Also, I think it is a good idea to treat practices the same as games, so if they get taped for one, they get taped for them all.
There are also varied opinions on whether or not braces better protect against ankle sprains. Some studies have shown that the tape on an ankle loosens and loses some of its support after just 12-20 minutes, depending on activity.
Braces on the other hand tend to not loosen to the same degree. The plus with braces is that if they do loosen up, all you have to do is tighten the laces or straps, where as with tape, you might get away with putting on a couple extra heel locks and stirrups and be good, but considering how often you would have to do it, by the end of practice or game it would be more like a cast than an ankle taping. That is why I prefer to use braces on my basketball players, ONLY IF the braces fit the athlete correctly. If the brace does not fit, then you are better off with the tape.
There is a lot of contradictory research out there on how ankle taping should be utilized. Some studies show that it decrease untaped proprioception of the athlete, while there are studies that show athletes with taped ankles receive less ankle injuries while taped than athletes without tape.
Below are some studies found on pubmed. There are 112 studies if you type in ankle taping.
Here is an abstract of a study talking about taping athletes with a history of ankle injuries and athletes without a history of ankle injuries on a cost-to-benefit analysis. The entire study can be found for free on pubmed.
Prophylactic Ankle Taping and Bracing: A Numbers-Needed-to-Treat and Cost-Benefit Analysis.
Olmsted LC, Vela LI, Denegar CR, Hertel J.
The Pennsylvania State University, University Park, PA.
OBJECTIVE: Taping and bracing are thought to decrease the incidence of ankle sprains; however, few investigators have addressed the effect of preventive measures on the rate of ankle sprains. Our purpose was to examine the effectiveness of ankle taping and bracing in reducing ankle sprains by applying a numbers-needed-to-treat (NNT) analysis to previously published studies. DATA SOURCES: We searched PubMed, CINAHL, SPORT Discus, and PEDro for original research from 1966 to 2002 with key words ankle taping, ankle sprains, injury incidence, prevention, ankle bracing, ankle prophylaxis, andnumbers needed to treat. We eliminated articles that did not address the effects of ankle taping or bracing on ankle injury rates using an experimental design. DATA SYNTHESIS: The search produced 8 articles, of which 3 permitted calculation of NNT, which addresses the clinical usefulness of an intervention by providing estimates of the number of treatments needed to prevent 1 injury occurrence. In a study of collegiate intramural basketball players, the prevention of 1 ankle sprain required the taping of 26 athletes with a history of ankle sprain and 143 without a prior history. In a military academy intramural basketball program, prevention of 1 sprain required bracing of 18 athletes with a history of ankle sprain and 39 athletes with no history. A study of ankle bracing in competitive soccer players produced an NNT of 5 athletes with a history of previous sprain and 57 without a prior injury. A cost- benefit analysis of ankle taping versus bracing revealed taping to be approximately 3 times more expensive than bracing. CONCLUSIONS/RECOMMENDATIONS: Greater benefit is achieved in applying prophylactic ankle taping or bracing to athletes with a history of ankle sprain, compared with those without previous sprains. The generalizability of these results to other physically active populations is unknown.
Here is another related study:
Effectiveness of taping and bracing in balance.
Barkoukis V, Sykaras E, Costa F, Tsorbatzoudis H.
Department of Physical Education and Sport Sciences, Aristotle University of Thessaloniki, Greece.
Taping and bracing are thought to be effective methods in restricting the ankle’s joint motion and assisting prevention of injuries. Research evidence suggests that taping and bracing enhance both the mechanical support and the proprioception of the ankle. However, there is little research concerning the influence of taping and bracing on sport performance. Research has mainly examined tasks with demands on the frontal plane. Therefore, the present study examined the effect of taping and bracing on the performance of a task with demands on the frontal plane. A sample of 30 physical education students (Mage=21.9 yr.) performed a balance task requiring estimation of balance and both right and left deviations. The subjects performed the balance task on four different conditions, with tape, with Swede-O (a lace-up, boot style stabilizer), with Aircast (an inflatable cast), and without any stabilizer. There were no significant differences among the conditions. These findings indicate that taping and bracing do not have negative effects on balance in the frontal plane. This study created concerns regarding the appropriate stabilizer for different tasks, bilateral coordination after the application of a stabilizer, and the influence of psychological factors on prevention of injury.