When taking a physical fitness test (PFT), you may recall giving all you have to max out the pushups, only to stop half-way up, shaking violently. No matter how hard you try in the next few seconds of the test, you are not going to get another pushup. That is muscle fatigue.
Here is a question about how to avoid muscle fatigue during fitness tests.
Stew – it does not matter on what exercise I am on, I can never keep going until the entire two minutes of the PFT is complete. On a good day, I might manage 1:30 of pushups or situps. I usually just shake and drop to my knees uncontrollably. Don't even ask how my bad days look. I would really like to score better on the PT test. I am a runner so the 1.5 mile run in 7 min mile pace is no problem. Jake
Jake – There are a few things that could be contributing to your fatigue or lack of muscle endurance (aka stamina) during the pushups and sit-up test.
1. Lack of Training
You need to up your training volume. I highly recommend doing pushups, sit-ups, pullups, and other core exercise (planks, etc.) three days a week. For example, if you have never done 100 pushups or sit-ups in an entire workout, you will never get 100 reps in two minutes. Try to build up over time to 2-3 times your goal maximum score during a workout. For instance, if your goal pushups max is 50 in 2 minutes, shoot for 100-150 during a normal workout. (See workout ideas for every OTHER day: PT Pyramid, PT SuperSet, Max Rep Sets). Also, stretch out your sets to 1-2 minutes in length on Max Rep Set Days.
2. Pace Yourself
Too many times people start out way too fast on these exercises only to burn out in the first minute. Pacing your running makes sense to you, right? You do not start the run in a sprint of your first lap (1/4 mile) -- you have a set pace. The same holds true for exercises like sit-ups. Too many people start off in the first 30 seconds getting 30-35 sit-ups and fail to match that in the next 1:30. If you are stuck at 60 due to this, you can increase your score near overnight by dropping your pace to 20 reps in the first 30 seconds and push closer to 80 reps in 2 minutes. For pushups -- that is a different animal, as you have gravity slowly eating away at your reps the slower you go. I recommend you let gravity take you down and exert fast on the up movement. Don't waste energy going down when gravity will do that for free. Keep working your pace in the workouts and you will find that you have the stamina to go the full 2 minutes after a few weeks.
3. Fuel and Fatigue
Half of fatigue is in your mind, as your brain will tell you that you are finished before you really are. The other half of fatigue is in your fuel. Did you eat well the day before or the morning of the fitness test? Are you hydrated? Having your body well fueled will help you with PT tests -- that means nutritious foods. However, when you start to shake at the end of your pushup timed set, you are going to waste a lot of energy fast, as that is a central nervous system breakdown (or the beginning of it). It is actually best to call it quits and not try to get that last pushup in, versus staying there and shaking for 10-15 seconds. You have to remember that you still have to do the 1.5 mile run next, and you will need that energy your body just dumped failing at pushups.
Practice taking the fitness test once every week or two just so you can also mentally say to yourself, "this is just another workout." Getting rid of some of the PFT Anxiety might help you perform a little better as well. Eat well and workout regularly, so that 1-2 minute sets become easy instead of an impossibility. Check out the PFT Bible if you are interested in a program that is specifically designed for the most common PFT in the world.