With your reference guide to workout terms thoroughly absorbed (or at least nearby for reference), the following workout routine has proven to myself and others to be the most time efficient effort/time invested for the results.
Having a workout buddy can help to make the workouts more intense without compromising form or safety. inbox me if you want to know more about spotting to get more out of workouts or about workout partner etiquette.
ALWAYS RESEARCH, CONSULT YOUR DOCTOR AND/OR GYM INSTRUCTOR BEFORE TAKING ON NEW EXERCISES.
The Twice-A-Week Warrior Workout:
This workout involves up to 50 minutes of workout time and is split into Upper and Lower Body sessions.
Synopsis: For each major muscle group you will perform 5 sets of one exercise, with the last set incorporated into a 'Kill Set' with a different movement at a lower weight and higher reps.
Goal: Set one, higher rep range and low weight helps to warm and prepare the muscle group. Sets two, three, and four increase the intensity and encourage blood flow to the muscle group. Set 5 is the highest intensity, perhaps 80-100% of total potential output, followed by kill set that burns out the muscle and triggers catalysts for muscle fibre tears.
When deciding on your weight, calibrate. On the first day go very light and increase the weight per set only moderately. Do not get caught up in your amazing ability to defy gravity with your muscles, and KEEP YOUR EYE ON THE CLOCK WHEN YOU'RE ON YOUR REST BREAK! NOT THE BOOTY ON THE TREADMILL!
Know this: The numbers are fake. They are for the guy in his 20's who has never been in the gym. All weights are meant to be an example of progression. Each workout's accomplishments should be written down and attempts to meet and exceed the prior workout's performance should be the goal. Start at your own pace, and start light. If you didn't get anything out of it, raise the weight again. Being superman can literally get you killed at the gym, and no one wants to see that.
Sample Upper Body Workout:
Dumbbell Benchpress: 12 reps at 20lbs each. Rest 1min. 10 reps at 30lbs each. Rest 1min. 8 reps at 40lbs each. Rest 1 min. 6 reps at 50lb each - no rest - immediately move to dumbbell flyes for 12 reps at 25lbs each
Dumbbell Shoulder Press: 12 reps at 10lbs, Rest 1min. 10 reps at 12.5lbs, Rest 1min. 8 reps at 15lbs. Rest 1min. 6 Reps at 17.5lbs - no rest - immediately move to dumbbell side-raises 12 at 7.5 or 10lbs.
Seated cable row: 12reps at 30lbs, Rest 1min. 10 reps at 40lbs each. Rest 1min. 8 reps at 50lbs each. Rest 1 min. 6 reps at 60lb each - no rest - immediately move to Cable Lat Pull-downs for 12 reps at 30lbs each
Assisted Dips (counterweighted)
12 reps at 20lbs Rest 1min. 10 reps at 30lbs Rest 1min. 8 reps at 40lbs. Rest 1 min. 6 reps at 50lb - no rest - immediately move to Overhead Dumbbell Curls for 12 reps at 10lbs each
Close-grip Barbell Raises:
12 reps at 20lbs Rest 1min. 10 reps at 30lbs. Rest 1min. 8 reps at 40lbs. Rest 1 min. 6 reps at 50lb - no rest - immediately move to Alternating dumbbell hammer curls for 12 reps at 20-25lbs each
Estimated Time: 50 Minutes
Sample Lower Body Workout
Seated Leg Press Machine: 12 reps at 50lbs. Rest 1min. 10 reps at 70lbs. Rest 1min. 8 reps at 90lbs. Rest 1 min. 6 reps at 110lb - no rest - immediately move to Leg Extensions for 12 reps at 25lbs for each leg
Stiff-legged deadlifts: 12 reps at 50lbs. Rest 1min. 10 reps at 70lbs. Rest 1min. 8 reps at 90lbs. Rest 1 min. 6 reps at 110lb - no rest - immediately move to Leg curl machine for 12 reps at 25lbs for each leg.
Raised 2-legged calf raises on smith machine:
2 reps at 20lbs Rest 1min. 10 reps at 30lbs. Rest 1min. 8 reps at 40lbs. Rest 1 min. 6 reps at 50lb - no rest - immediately move to seated calf raises for 12 reps at 20-25lbs each
Total Estimated time: 35 minutes
This regimen should also incorporate cardiovascular activity on off-days, muscle soreness permitting. Also consider forearms, abs, and other supporting muscle groups (like inner and outer leg muscles and tendons) on off days.
Stretching muscles should be done thoroughly at least one full day prior to exerting it while the muscle is fully recovered, and only to relieve occasional discomfort during DOMS (delayed onset muscle soreness).
And I'm not kidding! Consult a trained professional before starting at the gym. Just man up and do it.