As you all know, we take everyone through a dynamic warm-up at the beginning of every class. This is necessary to get the blood flowing to the muscles and joints and the body "activated" for physical activity. After the warm-up, we then move on to the strength portion of the workout. We sometimes will have a percentage-based weight that is prescribed to each individual based on their 1-rep max for a certain amount of volume (sets/reps). I like to call those "work sets". The work sets, however, should be something you warm up to. The dynamic warm-up is a generic full-body warm-up; it does not necessarily prep the body for any particular exercise. Before your work sets, you should be taking some sets with a lighter load to prep the joints and nervous system to bear the weight of your work sets.
For example, if we have Back Squats for 4 sets of 5 reps at 75%, those 4 sets will be your work sets. Before that you should do something like the following:
Then you'll jump to 75% for your first work set. If you don't have the luxury of taking (almost) all even jumps to 75%, the rule of thumb is to take your bigger jumps early in your warm-up sets and as you move up in weight you'll take smaller jumps.
For example, let's say you have 4 sets of 4 at 80%:
You can see that the first jump after 50% was +15%, then the next was +10% followed by a +5% jump. If you take too big of a jump, then you'll wonder why we replaced all the 45lb bars with 100lb bars; in other words the weight will feel much heavier than it should simply because you didn't properly prepare the body to move that much weight — and when you don't properly prepare the body there's always a possibility for injury! Let’s talk about the jumps you should take when you’re working up to find a one-rep max. Still consider the rule of thumb previously stated in that you want to take your bigger jumps early.
Now, in our gym I don’t like people doing a set that is their current one-rep max; I want people to plan out their jumps to make sure they are going to jump over that number. One thing you can do is to figure out what weight you want to hit just before you jump over your current max and what number you are going to jump to. So if your current max is 265 lbs, let’s say you want to take 260 right before and you want to jump to 270 to beat it. Now that you have 260 just work backwards.
As always, if do any of these sets and they feel off or extra heavy at that time, there’s no rule saying you can’t take any warm up sets twice. Pay attention to how your body is feeling and make sure you are preparing your body properly. If you take jumps way too big and the same thing happens almost every single time...it’s going to feel like it’s twice as hard and you are going to be questioning yourself on whether or not you think a max is even a possibility. Typically when I catch this, I make the person do one or two more sets at that weight and then their body catches up to them to a point where that weight gets easier and easier. Now they are back on track to keep increasing. If the jump is that extreme they you may have to take some weight off and work back up slowly. So don't get in a rush and take your warm-up sets!