arduousness
strenuousness
laboured
facility
readiness
like it's going out of style
Sisyphean
someone's heart out
arduous
a hundred and ten percent
gruelling
hard
heavy
punishing
operose
laborious
lyricism
difficult
thinly
backbreaking
toilsome
grueling
sloggingly
prima donna
obsessiveness
obsessivity
lightweight
overeagerness
nitency
hyperingenuity
endeavor
efficiency
backbreaker
showoff
sweaty
pretentiously
spuriosity
overmasterfulness
struggle
drudging
labouring
arduously
one's socks off
toiling
fight
laboring
overearnest
winsomely
overventurous
adroitness