Fractional plates are an absolute must for the workout programs within this manual. You need to get several different sizes of fractional plates so you can make continuous progress on all the different exercises.
Some exercises use smaller amounts of weight and need smaller fractional plates. Other exercises use larger amounts of weight and need larger fractional plates. For example, take squats versus dumbbell curls. One exercise uses hundreds of pounds while the other uses tens of pounds.
Let's talk about why you need fractional plates…
One of the big reasons you need fractional plates are dumbbells. If you use dumbbells (which you should at some point), you can only take jumps in 10 pound increments or 5 pounds for each dumbbell. Those are HUGE jumps in weight for most dumbbell exercises.
There are magnetic fractional plates that you can attach to dumbbells making it easy to increase a pound, two pounds, etc until you get a much better weight increment.
With barbells, the smallest increase you can make with typical plates is 5 pounds or 2.5 pounds on each side. For many barbell execises, that's a huge jump in weight.
If you can continue adding small amounts to the bar or dumbbells, you can make strength gains for longer periods of time. Progress for longer periods of time is your goal.
If you make huge weight increases from workout to workout, you will most likely stall pretty quickly. For example, let's say you are doing alternate dumbbell curls with 30 pounds for 6 reps. You increase the dumbbells to 35 pounds. That's a HUGE increase in weight for such a small amount of weight being used.
If you are already close to your maximum strength levels on dumbbell curls and you make a HUGE increase like that, you're going to stall. Instead, you could have increased by just a pound, then another pound, then another pound, and so on until you exceed your previous best and you stall.
You will make better progress by using fractional plates when needed. That's all there is to it. Get yourself a good variety of fractional plates and use them when needed. Don't make large jumps in weight unless you're very experienced and know what you're doing. Larger jumps in weight between workouts can hurt your strength gain progress but help your muscle gains. But, you must know what you're doing so you don't stall out too fast.