Congestive heart failure patient blood pressure to high?

Patient already has begun stage four symptoms.Mostly left side failure.What's new is patient decides to use stationary bike to increase leg muscle strength.Suddenly his BP is 160/105 then after sitting awhile it returns to 134/74.My question is does the bicycle cause the blood pressure problem alone, or would his excessive salt intake be more likely the problem.Also the patient is has trouble relaxing at night and is very weak. Way too much salt intake.near normal weight.Entering fourteenth year of CHF. Pulmonary edema.77 years old.Thanks.