The incident occurred in Sirauli village as Mohit was practicing for a school sports competition set for December 7.
Mohit had completed two laps with his friends when he suddenly collapsed.
His friends alerted his family, who rushed him to a nearby hospital, but doctors declared him dead on arrival, officials said.
Tragedy had already struck the family earlier this year when Mohit's father died in a road accident in August, according to the police.
This is the latest in a series of similar incidents reported in Aligarh recently.
Last month, a 20-year-old woman, Mamata, suffered a heart attack and died while running in Arrana village.
Three more cardiac arrests have been reported in the past 25 days—an 8-year-old girl collapsed while playing in Lodhi Nagar, a doctor died at home while preparing for work, and Syed Barkat Haider, son of former AMU Vice Chancellor SM Afzal, also succumbed to a heart attack on November 20.
Heart attacks among young people have raised alarm in recent months.
In September, a 9-year-old girl in Lucknow died after collapsing on her school playground and being rushed to the hospital, where she was declared dead.