Hi Rod - Isn't getting older fun? I'm surprised your body waited this long to balk - mine started complaining before I was 50. I retired from a lifetime of running after my first round of hip replacements before age 55 - the surgeon was honest and said "you can wear these new hips out too." Arthritis and 2 lung diseases jumped in to offer their own challenges.

It sounds to me like you want to be the 80 year old who jumps in line at the Marine Recruiting booth at the fair and "shows them young 'uns" by doing pullups - you gotta listen to your body - so here's a question for you - would you walk up to the weight rack on your first day at the gym, load a set of barbells with your body weight and try to lift it? That's what your trying to do with pull-ups. Did that get your attention?

Now, let's talk about what you CAN do -
If it is tendonitis, get yourself to a rehab Physical Therapist - one who can evaluate you and your body mechanics, assess your strength, and give you a program to get started. It will seem silly, even wimpy at first, and mostly involve stretching and maybe some very light resistance with bands to start. Maybe some massage, Kinesio taping, heat and ice.

Once the healing is done, you'll start with baby steps - light weights, low reps, 2-3 times a week max, and only moving up SLOWLY - then you'll reach the limit that your (aging) body will tolerate.

Be sure to add a lot of stretching and strengthening exercises for ALL parts of your body from neck to toes - Senior Yoga (aka Chair yoga in some places) is my choice, modifying the routine to challenge myself. Also balance exercises. If you can take a few classes from a real instructor who teaches proper form, it is helpful. If not, You Tube is full of great examples - look for those that demonstrate proper form.

So here is an example, after 3 years of pain management PT plus years of experience, of my routine - Every morning 10 minutes of stretching before I get out of bed to loosen up arthritic joints. 3 days a week 45 minutes senior stretch & yoga, some seated, some standing, including 5 minutes of balance work. 2 days a week light weights and concentrated stretching of leg, thigh, hip and lower back. 5 days a week a brisk walk varying from 20 minutes to an hour. 2 days a week of rest from exercise.
Remember, house and yard chores like mowing, raking, gardening, mopping & vacuuming, hauling groceries, etc are also exercise. At 73, I will never be able to lift and toss my body weight like I could when I was 20, nor run a miles at 8 minutes a mile like when I was 40, but I plan to keep this mortal shell functioning for another 20 years or so...
How are your elbow doing?
Sue