Prepping for a whole new year

Turning 50, taking Tamoxifin and living without ovaries has put a whole new twist in my training. I have had to make some changes in my workout routines due to fatigue, interupted sleep, weight loss and strength loss. My first change is mixing up my strength routine. I have always been a big proponent of body weight exercises for endurance athletes; but with my big loss in strength, I have headed back to the weight room, hitting the machines and free weights. Here is my new program: Exercise DAY I; DAY 2; DAY 3 1. Plank 2 x 30-60 secs; 1 x 60-90 secs; 2 x 30-60 secs Low Back 2 x 15 - 15; 1 x 15; 2 x 15 - 15 (can be machine, superman's or swis ball reverse curls) Calf raises 1 x 25; 2 x 25; 2 x 25 - 20 2. Squats 2 x 15 - 13; 1 x 12; 1 x 15 Bench Pr. 1 x 15; 2 x 15 - 12; 1 x 12 Seated Row 1 x 15; 2 x 15 - 12; 1 x 12 3. DB step-back lunge 1 x 12 each leg; 1 x 12 each leg; 1 x 12 each leg DB pull-over 1 x 15; 2 x 15 - 12; 1 x 12 High Pulls 1 x 15; 2 x 15 - 12; 1 x 12 4. Leg Ext. 2 x 15 - 12; 1 x 12; 1 x 15 Leg Curls 2 x 15 - 12; 1 x 12; 1 x 15 Wide grip pull-ups 10-12; 12-15; 10-12 (I use the "assited" pull-up machine) 5. Bridge with ball and band (pulse-squeeze and push out 2 x 30 secs.) Single Leg Bridge 2 x 15 Dead lift 2 x 15 ***Group 5 is done on day 1, 2 & 3... Each group of exercises is completed as a circuit and then you move to the next. It runs a three-day pattern, sometimes one set, sometimes two. If two sets the second set of reps is with a heavier weight. I will complete this phase for another 4 weeks and then switch it up. I am now two weeks in.