Adjective: effortful e-fu(r)t-ful
See also: arduous, backbreaking, difficult, dragging, exhausting, grueling [US], gruelling [Brit, Cdn], hard, heavy, killing [informal], labored [US], labor-intensive [US], laborious, laboured [Brit, Cdn], labour-intensive [Brit, Cdn], leaden, operose, plodding, punishing, Sisyphean, straining, strenuous, tiring, toilsome, wearing, wearying
Antonym: effortless
Encyclopedia: Effortful