All reps are not created equal. Although every rep spurs growth, the final reps are by far the most important. The early part of each set warms you up and prepares you for the true challenge. As long as the final rep has you grind against a fairly heavy resistance, you can end with this set and finish your exercise completely.
Many trainees cut this final rep. They end with a perfect full-range of motion rep without much of a struggle, either on purpose or because they are a coward. They shortchange their results and have less clear feedback regarding their real level of progress, never really knowing where they stand.
Keep pushing on that final rep, even if you slow down to almost a halt. You will surprise yourself most times and get that finisher if you continue to push or pull with all your might. You may continue to progress without training to failure for quite some time, but will lose a barometer for progress while ignoring that someday you will need to extend past your limits when things get tougher.
If the battle for civilization comes down to the wimps versus the barbarians, the barbarians are going to win.
– Thomas Sowell
- A slow speed allows higher tension.
The slow-up that occurs when fighting against a seemingly heavier weight requires you to work as hard as possible to keep moving. This utmost effort recruits the fast-twitch muscle fibers most responsible for size and strength. The actual slow speed, despite your best effort to go fast, allows the max number of cross-bridges or connections to form within your muscles. This tension leads to better results. Going too quickly will allow too little time for many sites to form. You only could go too quickly when you fail to work hard. The combo of hard work and slowness leads to max stimulation.
- Recruits the fast-twitch muscle fibers.
Muscle fibers work in a ramp-like pattern and activate as needed. The fast-twitch muscle fibers only play a role in fast or heavy activities, but the intention of speed and feeling of heaviness matters more than the actual speed or weight.
As long as you use a decent weight that prevents getting out-of-breath or too much lactic acid from stopping you in your tracks, all the fibers will work. Training to failure makes sure that you have recruited all of the fibers. On high rep sets, the fast-twitch muscle fibers take longer to recruit. Going for that last rep ensures the fast-twitch fibers played their part in the dance.
If you choose to avoid the hardest reps then you have to use much heavier weights that guarantee these fibers enter, perhaps a level of resistance that may feel unsafe.
- May induce a powerful hormone effect.
Your body aims to survive. Going for an excruciating rep presents a great challenge to your body’s status quo. With adequate rest and nutrition, you can recover and thrive from this super-stimulus.
Training hard releases more hormones. These allow for more force, energy, and focus. Testosterone and growth hormone increase which may lead to more long-term growth.
This process can inflict stress on your body as well so make sure you recover well.
- Builds character.
Going all-out teaches you the skill of how to work hard. As the weights progress, reaching goals grow harder and harder. You have to dig deep down to continue getting better.
Without going to your max, you never know your potential and may find yourself performing well below your capability.
You can also apply this exceptional courage you gain to defeat anything else in life that attempts to stop you.
- Ensures progression.
Fighting with that final rep ensures you truly do everything possible to go up in weights or reps over time.
How do you know where you stand without that final rep? Did you apply 90 % effort, or maybe only 50? Without your best effort, how can you judge the success of your program? Are all the variables just right?
You do not need to go to failure to progress but doing so will ensure you did everything you could.
- Recruits more muscle.
On the biggest, safest, and best compound movements, the larger muscles can take over.
The body has a tendency to focus on the largest muscles during any exercise as an energy conservation method. Without hard training, you may not recruit the smaller movers as equally as the big muscles, although choosing the right grip or stance usually mitigates against this possibility.
A bench press without enough effort may only be felt as a chest exercise when you should also feel the shoulders and triceps working intensely as well.
A last-ditch effort also forces your body to tighten up. This tightening works smaller stabilizers. Think if it like squeezing your fist as tight as possible. The tension radiates out to other muscles the harder to squeeze. This same process happens when any muscle works at its limit.
Although many think of pull-ups as a back and arm exercise, it will tax your core and grip as well but only if you give it everything you got. This shows the power that hard training has on your whole body. It makes every system work harder.