Some sort of a warm-up prior to lifting is important. It should stimulate you without feeling too exhausting. You can go about this in several ways though.
Many avoid warm-up sets of any rep count over 5. Some experts argue that too long a warm-up set will fatigue you before the tough sets. They instead suggest multiple sets of low reps. Each subsequent set uses a larger percentage of the target weight for the exercise. Here is an example, but many lifters will add even more sets than listed:
- 30% of the target weight for 5 reps.
- 60% of the target weight for 5 reps.
- 80% of the target weight for 5 reps.
- Working sets.
The increase toward heavier weights on each set aims to prime the nervous system. It prepares you for your best effort by activating the fast-twitch muscle fibers. You also gain more practice with weights closer to your maximum.
Besides inefficiency due to the many sets, which can lead to overtraining, this plan has flaws. The heaviest sets, even for low reps, can fatigue you much more than high rep sets. The biggest factor for lifting progress is tension, the main stimulus for more size and strength, which gets reduced by heavy weights. Hitting the fast-twitch muscle fibers during the warm-up will reduce your tension on the sets that count.
Another Plan
Instead, we want to prepare the muscle as a whole without reducing tension on the working sets. Consider warming up with a single set of higher reps, with any number of reps between 8-12 for 60% or less of your target weight working well. This will improve blood flow more so than lower rep sets.
A warm-up has proven value for preparing you by increasing your body’s temperature, but you need enough blood flow to gain it. With enough blood, you will feel loose and more powerful. With too little of a warm-up, which may occur with low reps, you apply effort on the hard sets with cold muscles. Would you expect to sprint at your top speed right away upon rising from a chair after sitting for a few hours?
Many worry that these longer warm-up sets will fatigue you. Lactic acid in the form of lactate, which does interfere with muscle contraction, cannot build up much until sets last 1-3 minutes. A set of 8-12 reps at a good speed, neither too fast nor too slow, will last less than a minute.
Example
If your goal was to bench press 200 lb. for 5 reps, you would perform a warm-up with 100 lb. for 8 reps instead of multiple sets of 5.
Many benefit from the concept of auto-suggestion, or performing the same number of reps for both the warm-up and working sets to build confidence.
Performing more reps on your warm-up than your working sets can also give you this boost.
Consider More Reps on Warm-Up Sets
No amount of experimentation can ever prove me right, a single experiment can prove me wrong.
– Albert Einstein
Warming up is a unique process for each trainee. Some people prefer longer and others want it briefer. As a rule, always do the least amount of exercise to achieve your goal. Find your own balance. Use your progress log to analyze if a change works. Consider a higher rep warm-up set to boost your performance.