1) Affected 2) Applied elbow grease 3) Artificial 4) Awkward 5) Done with excessive effort 6) Exerted great effort 7) Exerted oneself 8) Forced 9) Labored 10) Laboured 11) Lacking natural ease 12) Lacking spontaneity 13) Like some relations 14) Not exactly friendly 15) Not natural 16) Not natural or spontaneous 1) Constrained 2) Farfetched 3) Filtered 4) Haggard 5) Harassed 6) Labored 7) Laboured 8) Overstrung 9) Plttk 10) Pureed 11) Stressed 12) Taut 13) Taxed 14) Tense 15) Tensed 16) Tried 17) Sforzando 
• (a.) Done or produced with straining or excessive effort; as, his wit was strained. • (a.) Subjected to great or excessive tension; wrenched; weakened; as, strained relations between old friends. • (imp. & p. p.) of Strain
Strained adjective 1. Subjected to great or excessive tension; wrenched; weakened; as, strained relations between old friends. 2. Done or produced with straining or excessive effort; as, his wit was strained . 
[adj] - under great stress
adjective under great stress; `her voice was strained as she asked the question`
affected or produced by effort; not natural or spontaneous; forced: strained hospitality.