Photos and video of these exercises are widely available on the Internet through YouTube or such sources as the American Council on Exercise’s Exercise Library at www.acefitness.org.

First quarter:

Three rounds of

1. Squats (12-15 reps)

2. Plank hold (30 seconds; can be done on hands or forearms, knees or feet)

3. Bosu ball squats (12-15 reps; the Bosu adds a balance component to the squats, which encourages good form and posture)

(Illustration by Rachel Harris)

←4. Hip bridges (12-15 reps; hold three seconds at the top)

Rest one minute between each set.

Second quarter:

Try increasing the challenge when possible by using small dumbbells or a medicine ball (5-15 pounds).

Three rounds of

(Illustration by Rachel Harris)

1. Alternating lunges (12-15 reps for each leg)

2. Push-ups or floor press (12-15 reps)

3. Mountain climbers (15 reps for each leg)

4. Bent-over row (12-15 reps)

Third quarter:

Three rounds of

1. Walking lunges with weights
(8-10 reps per leg)

(Illustration by Rachel Harris)

←2. Sitting military press with
dumbbells (8-10 reps per side)

3. Seated row with a resistance
band
(8-10 reps)

4. Lying dumbbell chest press (8-10 reps)

Fourth quarter:

Heavy lifts. To stay safe, consider having a trainer check your form.

Three rounds of

1. Back squat with barbell (6-8 reps)

2. Bench press (6-8 reps)

3. Deadlift (6-8 reps)

(Illustration by Rachel Harris)

4. Standing barbell press (6-8 reps)

— Gabriella Boston

Read more: 12 months to a fitter you