Introduction: "This 4-day upper/lower split workout program is designed to help you build strength and muscle by focusing on both upper and lower body exercises. By alternating between upper and lower body days, you can train with higher intensity while giving each muscle group the time it needs to recover. Let’s dive into the program!"

Day 1: Upper Body - Strength Focus

1. Warm-Up:

   • 5-10 minutes of light cardio (e.g., jogging, cycling, or rowing)

   • Dynamic stretches focusing on the upper body

2. Barbell Bench Press

   • 4 sets of 6-8 reps

   • "A classic compound movement that targets the chest, shoulders, and triceps. Focus on controlled movements, lowering the bar slowly, and pressing up explosively."

3. Weighted Pull ups (or Lat Pulldowns)

   • 4 sets of 6-8 reps

   • "Great for building back width and biceps. Use assistance if needed, and aim for a full range of motion, pulling your chest up towards the bar."

4. Overhead Barbell Press

   • 3 sets of 6-8 reps

   • "Targets the shoulders and triceps. Keep your core engaged to prevent arching your back as you press the bar overhead."

5. Barbell Row or Rowing Machine

   • 3 sets of 8-10 reps

   • "Strengthens the upper back. Keep your back straight and pull the bar towards your lower chest."

6. Dumbbell Bicep Curls

   • 3 sets of 10-12 reps

   • "Focus on controlled movements to target the biceps effectively. Squeeze at the top of each rep."

7. Tricep Dips (or Tricep Pushdowns)

   • 3 sets of 10-12 reps

   • "Great for building tricep strength. Keep your elbows close to your body and lower yourself slowly."

8. Cool-Down:

   • 5-10 minutes of stretching, focusing on the chest, back, shoulders, and arms.

Day 2: Lower Body - Strength Focus

1. Warm-Up:

   • 5-10 minutes of light cardio (e.g., brisk walking or cycling)

   • Dynamic stretches focusing on the lower body

2. Barbell Squats

   • 4 sets of 6-8 reps

   • "The king of lower body exercises. Focus on proper form: keep your chest up, core tight, and drive through your heels."

3. Romanian Deadlifts

   • 4 sets of 6-8 reps

   • "Targets the hamstrings and glutes. Keep a slight bend in your knees, hinge at the hips, and maintain a straight back."

4. Leg Press

   • 3 sets of 8-10 reps

   • "A great way to isolate the leg muscles. Push through your heels, and avoid locking your knees at the top."

5. Lunges

   • 3 sets of 10 reps per leg

   • "Lunges build leg strength and balance. Step forward with one leg, lowering your hips until both knees are bent at a 90-degree angle."

6. Leg Curls

   • 3 sets of 10-12 reps

   • "Targets the hamstrings. Focus on controlled movements and squeeze at the top of each rep."

7. Standing Calf Raises

   • 3 sets of 12-15 reps

   • "Builds calf strength. Stand on a raised platform, let your heels drop, then push up onto your toes."

8. Cool-Down:

   • 5-10 minutes of stretching, focusing on the quads, hamstrings, glutes, and calves.

Day 3: Upper Body - Hypertrophy Focus

1. Warm-Up:

   • 5-10 minutes of light cardio

   • Dynamic stretches focusing on the upper body

2. Incline Dumbbell Press

   • 4 sets of 8-10 reps

   • "Focuses on the upper chest. Keep a controlled motion and squeeze at the top of each rep."

3. Seated Cable Rows

   • 4 sets of 10-12 reps

   • "Targets the middle back. Keep your back straight, pull the handle towards your waist, and squeeze your shoulder blades together."

4. Dumbbell Shoulder Press

   • 3 sets of 8-10 reps

   • "Works the shoulders. Keep a controlled motion, and avoid bouncing the weights at the bottom."

5. Lateral Raises

   • 3 sets of 12-15 reps

   • "Targets the shoulders for width. Keep a slight bend in your elbows and lift your arms to the side until they’re parallel to the floor."

6. Hammer Curls

   • 3 sets of 10-12 reps

   • "Great for building bicep and forearm strength. Keep your elbows close to your sides and curl with control."

7. Skull Crushers (Lying Tricep Extensions)

   • 3 sets of 10-12 reps

   • "Targets the triceps. Use a controlled motion and focus on the stretch and contraction of the triceps."

8. Cool-Down:

   • 5-10 minutes of stretching, focusing on the chest, back, shoulders, and arms.

Day 4: Lower Body - Hypertrophy Focus

1. Warm-Up:

   • 5-10 minutes of light cardio

   • Dynamic stretches focusing on the lower body

2. Front Squats

   • 5 sets of 8-10 reps

   • "Focuses more on the quads and core compared to back squats. Keep your elbows high and chest up to maintain balance."

3. Deadlifts

   • 5 sets of 8-10 reps

   • "Great for overall lower body strength, especially in the back and hamstrings. Keep your core tight and lift with your legs, not your back."

4. Leg Extensions

   • 3 sets of 10-12 reps

   • "Isolates the quadriceps. Focus on controlled movements and squeezing at the top."

5. Glute Bridges

   • 3 sets of 10-12 reps

   • "Targets the glutes and hamstrings. Lift your hips towards the ceiling and squeeze your glutes at the top."

6. Seated Calf Raises

   • 5 sets of 12-15 reps

   • "Focuses on the lower part of the calf muscle. Use a full range of motion to maximize contraction."

7. Cool-Down:

   • 5-10 minutes of stretching, focusing on quads, hamstrings, glutes, and calves.

Tips for Success

• Rest: Make sure to rest for 1-2 minutes between sets to maintain intensity, especially during strength-focused days.

• Progressive Overload: Gradually increase the weight or reps each week to keep challenging your muscles.

• Nutrition: Support your training with a balanced diet rich in protein, carbohydrates, and healthy fats to fuel muscle growth and recovery.

• Consistency: Stick to the routine for at least 4-6 weeks to see results, adjusting as necessary based on your progress and goals.

This 4-day upper/lower split program offers a comprehensive approach to building muscle and strength. By focusing on both strength and hypertrophy, you’ll be able to develop a well-rounded physique. Enjoy your workouts, and stay consistent!