Abbreviated first person singular ending

Question

I noticed an acceptable alternative of the first person singular verb ending. I don't know if

1. this is just an abbreviation or changes the meaning
2. is associated to aspect,
3. is associated to verbs of motion,
4. has analogues in other persons

e.g.

я бегу - я бегаю

Answer 1

These are 2 different verbs that form one of the pair of the verbs of motion.

Бежа́ть-бéгать

Бежа́ть: Я бегу, ты бежи́шь, он (она́, оно́) бежи́т, мы бежи́м, вы бежи́те, они́ бегу́т

Бе́гать: Я бе́гаю, ты бе́гаешь, он (она́, оно́) бе́гает, мы бе́гаем, вы бе́гаете, они́ бе́гают

Being the verbs of motion without prefixes, these verbs are both imperfective.The first one in the pair, "бежать" means "to run in one direction". The second one in the pair, бéгать means "to run somewhere and then return", "to run without any direction" pr "to run regularly".

All the verbs of motion work like that, the first verb means "to go, fly, swim, run, carry, etc. in one direction" and the second one, in two directions, way and back:

идти́-ходи́ть: go on foot плыть-пла́вать: swim лете́ть-лета́ть: fly е́хать-е́здить: go on transport, ride нести́-носи́ть: carry something on foot везти́-вози́ть: carry something on transport вести-води́ть: lead somebody