If you're looking for weights for a home gym, all you'll need when it comes to weights is dumbbell sets and barbell sets. From there, you can add extra weight plates.
For dumbbell sets, I highly recommend hex dumbbell sets if you have the space for a couple of dumbbell racks. This is the most expensive option and takes up the most space but also cuts down on your workout time by huge amounts. You simply grab the dumbbell you need and get to lifting weight with the exercise of your choice.
The only drawback of hex dumbbell sets is that the weight increments between dumbbells is 5 pounds. When using 2 dumbbells, this means the weight increase must be 10 pounds! This is a HUGE jump in weight for most dumbbell exercises. To counter this, you can use plate mates or micro gainz. These allow you to add a magnet to the side of the dumbbells or a very small weight plate around the handle, respectively.
If you don't like the hex dumbbell option with lots of dumbbells, there are very good adjustable dumbbell sets on the market now. Ironmaster is my favorite as you can add smaller weight plates for smaller increments in dumbbells. Very nice set.
Or, you can start as I did many years ago with a low cost adjustable dumbbell set. It's just a set of dumbbell handles and standard weight plates. The drawback here is the time it takes to adjust the weight of each dumbbell. You have to manually removed and add weight plates constantly between weight lifting exercises.
Once you have dumbbells, you need to get at least one Olympic barbell set. These usually come in 300-pound weight sets. The barbell is 45 pounds so you get 255 pounds of weight plates with the 300 pound weight set. This is good, but I recommend 2 weight sets so you have 2 barbells to work with. This is good for warming up for an exercise that is on the floor (like barbell rows) while you are doing your working sets of squats in the power rack. If you only have one barbell set, you constantly have to move the barbell from the floor to the power rack. This takes lots of time and effort. Just doing this can wear you out and take away energy for your workout.
This is all the weights you need for a home gym! Some dumbbells and some barbell sets will get you a very nice home gym. Then, you can add extra weight plates as needed. Fractional plates are always a great thing to add to your home gym.
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