About 10 months back I got a pull up bar set up at home.It was very thick.I had problems gripping it.I couldn't do a single chin up on it.However after several days of trying,I was able to do a chin up.Then I kept on practicing chin ups and after about 2 to 3 months or more(I am not sure),I could do about 9 chin ups at a time.But after that I lost interest in it and didn't practice it for about 6 to 7 months.A few days back I tried doing chin ups.I managed to do 6 and every next day the number is decreasing.Today I was just able to do 3.5.How can I again increase that number? For how much time should i practice? Should I practice everyday?I can understand that i can't do as many chin ups as before due to lack of practice but why is the number decreasing every next day?Please guide me.BTW my age is 16 if that matters.
Your workout's level of success depends on many variables, so don't deduce that you have serious problems after 4 days. It may be related to stress, insufficient sleep, some hard work you've done, and some days we are not at our best for no apparent reason.
Anyway, if your goal is to maximize your chin up reps while not doing other exercises, I recommend the following:
- Instead of doing a set every day, do 3-4 sets every other day. One set, especially with low amount of reps, is way too low volume & intensity for developing muscles & strength. When doing these sets, don't do your max every set, but try to find a number of reps that lets your success in all sets, perhaps (but not necessarily) failing in the end of the last set.
- In each set, target a higher reps range (if possible). In the beginning, the best approach would be using and assisted pull up machine (if handy), like this one:
- If using the machine, reduce the level of help from one session to another. if not, just follow the first clause and increase the number of reps when you feel ready (± twice a week).
But more than all of these, I strongly recommend you to change your goal. Chin ups are great but they definitely don't cover all the major muscles of your body, so unless you train for a "max chin ups" contest, you should go for a different program, which eventually will also lead in the long term to more reps in chin ups.
Since you've got a chin up bar at home, I'd recommend something like Pavel's Greasing the groove method.
I've used this in other exercises to great effect.
Basically, take half the maximum amount of chin ups you can do (note: chin ups are with your palms facing you in an underhand grip, pull ups are with your palms facing away with an overhand grip) and do that number of reps every time you walk past the chin up bar. If it's somewhere you don't walk past, then set an alarm and do it every hour. Essentially, do lots of mini sets constantly throughout the day.
The idea is to view this as practice. Strength is a skill, you need to learn the skill in order to improve. You want to get better at chin ups, then practice chin ups. You get better at a skill by constant practice, so you get better at chin ups by constant practice of chin ups.
I agree with the answers by Neria Nachum and Dark Hippo, but I think there's one very important aspect that might be the main reason for seeing diminishing strength and endurance from day to day. You simply shouldn't be doing this every single day. Physiological adaptations for strength are cued by resistance training, but the actual adaptations themselves occur during recovery. Directly after training there will be a period of lower performance, which must be recovered from. After recovery and adaptation you will be (slightly) stronger and can increase the workload. If you go right back to training those same muscles while they are in a state of decreased performance, you're piling fatigue on top of fatigue. Not only can recovery not occur this way, but the training itself will be inefficient since you can't reach a number of reps that would properly initiate an adaptation. So, wait about 48 hours between sessions to give your body a chance to recover and adapt.
See also this answer for a primer on the theory behind recovery: https://fitness.stackexchange.com/a/30030/19986