The phrase "a laborious exercise" is correct and usable in written English.
It can be used to describe a task or activity that requires a lot of effort and is often tedious or time-consuming.
Example: "Completing the lengthy report was a laborious exercise that took several days to finish."
Alternatives: "a tedious task" or "a strenuous activity".
Alternatively, to what extent do the tactics of political revolution imply a laborious exercise of their own?
A "Hail Mary" approach may work for a select few, but for others it can be a laborious exercise that may not even bear fruit.
But the government-dominated electoral authority disqualified 1.2m of them requiring those concerned individually to confirm their signature in a laborious exercise due later this month.
Despite it being "the band's heaviest, fulfilling many a fan's wish for sustained metal", Popoff finds "the whole thing perched on the edge of parody, too dressy and fantastical lyrically in a painfully self-conscious way, a laborious exercise in expected weird", ultimately "a baffling yet anticlimactic punctuation to the band's perplexed career".
Although parameters derived from such TF-gene binding assays are available in some databases, it would be a laborious exercise to obtain these values for every TF-gene pair [ 25].
The murder trial of a silent defendant, especially one who has spent a lifetime lying to everyone about almost everything, can't help but strike a child as what it is: a hugely laborious exercise in trying to read a mind.
For example, the unit "When I have to walk up and down the stairs, I move up the stairs in a sitting position and then I'm very short of breath" was interpreted in the following way: "Going up the stairs is a difficult and laborious exercise, which causes shortness of breath".
Although a time consuming and laborious exercise, the act of converting literature derived knowledge into a formalised computational models is essential if we wish to truly gain a systems level understanding of any cellular system.
The purpose of this slightly laborious exercise?
We therefore did not pursue assessing our hypothesis using the more costly and laborious exercise of infecting cell lines expressing CXCR4 and CCR5.
Although the Lacedaemonians have not fallen into this mistake, yet they brutalize their children by laborious exercises which they think will make them courageous.
