diff --git a/NonLinearSolver/materialLaw/mlawHyperelastic.cpp b/NonLinearSolver/materialLaw/mlawHyperelastic.cpp
index 94bb565dcf7eced452ed820356b44add1813b196..50a6486a3a8697e4088b0bd6c7b30c5156b6010b 100644
--- a/NonLinearSolver/materialLaw/mlawHyperelastic.cpp
+++ b/NonLinearSolver/materialLaw/mlawHyperelastic.cpp
@@ -143,9 +143,9 @@ double mlawHyperViscoElastic::deformationEnergy(const IPHyperViscoElastic& q) co
     double Av, dAv,B_d;
     static STensor3 dB_d;
     evaluatePhiPCorrection(trEe, devEe, Av, dAv, B_d, dB_d);
-    Psy = getUpdatedBulkModulus(&q)*Av*(0.5*trEe*trEe)+getUpdatedShearModulus(&q)*B_d*STensorOperation::doubledot(devEe,devEe); //this is not correct we should do an integral
-    
-
+    Psy = getUpdatedBulkModulus(&q)*(1.+Av)*(0.5*trEe*trEe)+getUpdatedShearModulus(&q)*(1.+B_d)*STensorOperation::doubledot(devEe,devEe); //this is not correct we should do an integral
+																// 
+																//    
     for (int i=0; i<_N; i++){
       static STensor3 devEebranch;
       Psy += _Ki[i]*0.5*(q._B[i])*(q._B[i])+_Gi[i]*STensorOperation::doubledot(q._A[i],q._A[i]);