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  7. Boat Stretch

Exercise guide

Boat Stretch

  • Intermediate
  • Compound
  • Timed hold
  • Waist

The Boat Stretch is a powerful isometric core exercise that simultaneously develops abdominal strength and improves flexibility in the hamstrings and hip flexors. It challenges balance and stability while promoting spinal alignment and postural control.

Reviewed by the Crucible team · Updated June 2026

Watch the Boat Stretch demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Abs
  • Hamstrings

Secondary

  • Obliques

Equipment

  • Body weight

Setup

  1. Sit on the floor with your knees bent and feet flat on the ground.
  2. Place your hands lightly behind your thighs or on the floor beside your hips for initial support.
  3. Lengthen your spine and draw your shoulder blades down and back to create a tall, upright posture.

How to do it

  1. Engage your core and lean back slightly, shifting your weight onto your sit bones as you lift your feet off the floor.
  2. Slowly straighten your legs to a 45-degree angle, creating a 'V' shape with your torso and thighs.
  3. Extend your arms forward, parallel to the floor, with your palms facing each other.
  4. Inhale deeply into your ribcage and exhale as you tighten your abdominals, holding the position with a steady tempo.

Form checklist

  • Keep your chest lifted and avoid rounding your lower back or shoulders.
  • Maintain a neutral neck position, gazing toward your toes.
  • Keep your legs squeezed together and your quadriceps engaged.
  • Ensure your weight is balanced on your sit bones rather than your tailbone.

Pro tips

  • Focus on the 'V' shape; if your back begins to round, slightly bend your knees to prioritize a straight spine over straight legs.
  • Imagine pulling your belly button toward your spine to maximize deep transverse abdominis engagement.

Make it harder

  • Transition into 'Low Boat' by lowering your legs and torso until they are just a few inches off the floor, then return to the high position.
  • Hold a light weight or medicine ball with both hands to increase the torque on the core.

Frequently asked

What muscles does the boat stretch work?
The boat stretch primarily targets the abs and hamstrings, and also works the obliques as secondary muscles.
What equipment do you need for the boat stretch?
The boat stretch requires no equipment — just your body weight.
Is the boat stretch good for beginners?
The boat stretch is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Alternate Single Leg Raise PlankIntermediate · abs, deltoids, hamstrings, and obliques
  • Alternating Child To Downward Dog To Body RockIntermediate · abs, calves, hamstrings, and lats
  • Alternating Hamstring Curl JackIntermediate · abs, glutes, hamstrings, and quadriceps
  • Alternating Hamstring Curl Overhead ClapIntermediate · abs, glutes, and hamstrings

Train this with a plan, not guesswork

Crucible builds the boat stretch into a precise program around your body, equipment, location, and time.

Download on the App Store