Sri Lanka are scheduled to play 15 Tests and 42 One-dayers during this period. The number could increase if a postponed series of five One-day Internationals against India goes ahead.
"It's going to be hard on players," Atapattu said on Thursday. "It's not going to do any good to their fitness.
"Generally, we play 25 One-dayers and 10 Tests a year and get a break of about three months. But this is something very unusual."
Sri Lanka begin the new season in July with a two-Test home series against the West Indies. The two teams will be joined by India the following month for a triangular One-day tournament.
They are then scheduled to tour India, Pakistan, Australia, England and Bangladesh for either Tests or One-dayers in the next 12 months.
"We were out of the country for more than nine months in 2002. This season is also going to be the same. I hope it does not happen every season," said Atapattu.
Some of the Sri Lankan players are also expected to represent a World XI in the International Cricket Council (ICC) Super Series in Australia in October.
"But there is nothing we can do about it," said the Sri Lankan skipper.
"We need to follow the ICC fixtures as it is our profession.
"There were a couple of series that got cancelled last year, like the one in New Zealand, and I suppose all those add up to this season."