While training a pokemon is all well and good, it takes time. Time you may not find you have. Fortunately, there are aides to help you get your pokemon’s EVs to where you want them.
The first and easiest aid to use is the set of Vitamin items- HP Up, Protein, Iron, Calcium, Zinc and Carbos are for HP, Attack, Defense, Special Attack, Special Defense, and Speed respectively (which means, in the same order). Despite what they appear to do, and what the text in the game says, these items do not directly boost the stat they are relevant to. Instead, each item gives 10 EV points to the stat in question. This is an amazingly useful way to save time, although the vitamins tend to be a bit expensive to purchase. And they will save you a lot of effort and battles- but there is a problem. You see, no vitamin will increase the number of EV points in a stat beyond 100. If your pokemon has 95 EV points invested in Health Points and you give it an HP up, it will only gain 5 EV points. So while the vitamins will drastically cut down on the amount of time it takes to get your EV points to where you want them, you simply can’t do the whole job that way.
This is where a few particular hold items come into play.
First of all, there is the oldest of the hold items relating to EVs- the Macho Brace. The Macho Brace is a strange little hold item- its most noticeable effect is that a pokemon who is holding it has their speed cut to ½ of its value when determining who acts first in a round of combat. This can be crippling in the wrong situation- but there’s no arguing with the beneft of the Macho Brace: A pokemon holding a Macho Brace at the end of a fight gains its EV points from whatever got knocked out -twice-. So if it would have gained 2 Special Attack points, it instead gains 4, just to give an example. This is decently useful, and cuts the number of battles you need in half- but you need to make absolutely sure, still, that you’re fighting the right things. And while cutting the number of battles in half is nice, if you’re cutting 510 to 255, you’re still looking at a huge amount of training to do and a lot of time to invest.
Fortunately, there are also the ‘Power Items’. The Power Weight (HP), Power Bracer (Att), Power Belt (Def), Power Lens (Sp. Att), Power Band (Sp. Def), and Power Anklet (Spd) are present in the fourth and fifth generation games to give you even more acceleration. What do these items do? Well, a pokemon holding the relevant item when an opponent is knocked out that gained EV points from that opponent will gain, in addition, four EV points for whichever stat the item applies to. This is an extra amount of EP, and is a much bigger acceleration than the simple doubling that the Macho Brace provides- and is an invaluable benefit to training. Cutting your training time in 1/4 or even 1/5 in the right situations, the Power Items have made training your EVs from a huge and massively time consuming messy business into a much neater and simpler chore of a far more acceptable size.