TheFittingPhysique: Legs and Core, Don't Neglect Them!

Legs
Benefits of doing legs:
for upper body growth (works the whole body/ allows it to grow proportionately as your upper body can't grow bigger if your base is small),
fat burn/metabolism increase, stability, explosiveness,
increase muscle growth hormones throughout the entire body (anabolic)

Leg exercises: squats, lunges or split squats(walking/stationary), deadlifts, leg extension, lying leg curls, calf raises(seated/standing)

a sample leg routine:

Barbell Squats

(Variations: Dumbbell Squats, Front Barbell Squats)

Leg Extension Machine

Both the above exercises targets the thighs, also know as quadriceps
another good exercise is the leg press machine.
Squats also help with the gluteus, also known as the butt muscles, allowing you to build a firmer buttock.

Deadlifts

(Variations: Stiff-leg deadlifts, Romanian deadlifts)

Lying Hamstring Curls

(Variations: Seated Hamstring Curls)

The above two exercises works the hamstrings.
While deadlifts hits the hamstrings,
it also emphasises a lot on the lower back and core to keep the body flexed and stable.

Standing Calf/Calves Raise

Do 3-4 sets of each exercise, 15-20 reps with no more than 2mins rest between sets.
Feel free to rearrange the order each session or vary the exercises/reps/weights.

Core

Benefits of doing core:
stability, strength, it's the centre of all our movements/center of gravity, prevent injuries (lower back, spine, pelvis, shoulders) with strong core muscles.

Core exercises: planks, deadlifts, squats, mountain climbers, crunch/reverse crunch, tucked L-seat/L-seat, tucked lever, oblique twists

a sample core routine:

Start with

Planks - 60 to 90secs

Side planks - 60 to 90secs for each side

Do this

Crunches - 15 reps
Mountain Climbers - 20 secs
Reverse Crunch - 15 reps
Mountain Climbers - 20 secs
Oblique twists/bicycle crunches - 20 reps(10 reps each side)
Repeat 3 times as a circuit with 90-120secs rest.

End off with
Planks - 60 to 90secs
Side planks - 60 to 90secs for each side