coumadin, blood pressure medication, and excerize

My father, 62 has had 4 episodes of arhythmia over the past 3 year, two of which required electrical shocks to get back in place.  He has been taking Coumadin since May '99, the time of the last shock treatment.

The current prescription calls for 5 mg tablets daily, with  1.5 tablets taken on mondays and thursdays.  He is also taking Amidorane @ 200 mg daily, as well as the following blood pressure medications:
Cartia XT - 180 mg daily
Tenex - 1mg daily
Monopril - 20 mg daily.

My father is scheduled to retire and wants to return to a rigorous exercize program that includes weight lifting, stairmaster and biking.   I have a couple of questions:

1) Is there any risk associated with excersize, especially when taking Coumadin?

2)In your opinion are the amount of drugs being taken considered to be excessive?

3) Coumadin appears to be a very dangerous medication that has risks when taken inproperly or with other medication. Are there alternative drugs avaialble that provide the same benefit, with less risk?

[Cleveland Clinic, MD]

Coumadin (generic name Warfarin) is a anticoagulant (blood thinner) that is used for a variety of conditions.  Common reasons for coumadin use are in atrial fibrillation to reduce the risk of stroke, in persons with clotting disorders, in persons with mechanical heart valves, and sometimes in people with severe heart failure.  The usual dosage is somewhere between 1 and 15 mg a day.  Potential side effects include bleeding, hair loss, nausea, vomiting, stomach cramps, diarrhea and leukopenia (low blood cell count).  The half life (amount of time for half the drug to be cleared from the body is 42 hours but varies widely depending on the individual).  

Many drugs interact with coumadin and may cause more anticoagulation effect (clofibrate, diazoxide, ethacrynic acid, nalidixic acid, phenylbutazone, salicylates, aspirin, sulfonamides, alcohol, allopurinol, amiodarone, cimetidind, phenytoin, erythromycin, gemfibrozil, propranolol, thyroid drugs) or decreased anticoagulation effect (smoking, estrogens, vitamin K, aluminum hydroxide - antiacids, cholestipol, spironolactone).  See complete list below.  The effects of coumadin must be carefully monitored by a blood test called an INR.  Usually this is checked more often at the onset of taking the drug and less often once a steady state has been reached.  Therapeutic INR is usually 2 to 3 depending on the condition being treated.

Pregnant women and those with a hypersensitivity to coumadin should not take this medication.  

The medication should not be taken with food and any signs of bleeding should be reported to your doctor.  Use a soft toothbrush, avoid hazardous activities, carry Medi-Alert ID identifying drug useage and notify your doctor if you have any dark brown urine or red or tarry black stools.

Known Drug interactions with Warfarin
Increased Effect :

                       Highly Probable

                            Alcohol (if concomitant liver disease)
                            Amiodarone
                            Cimetadine
                            Clofibrate
                            Cotrimoxazole
                            Erythromycin
                            Fluconazole
                            Isoniazid
                            Metronidazole
                            Miconazole
                            Omeprazole
                            Phenylbutazone
                            Piroxicam
                            Propafenone
                            Propanolol
                            Sulfinpyrazone

                       Probable

                            Acetaminophen (Tylenol