The Sternum Strap: A Useful Accessory for Rucking Comfort and Safety

Shoulders bear the brunt of the weight while rucking, but the core muscles also work hard to keep the body stable. Using a sternum strap, also known as a chest strap, is one way to increase comfort and reduce strain when rucking with a heavy pack.

What Is a Sternum Strap? Understanding Its Role in Rucking

A sternum strap, also referred to as a chest strap, is an adjustable accessory that connects the shoulder straps of a rucking backpack across the chest. Typically 1-2 inches wide and constructed from durable nylon webbing, sternum straps play a pivotal role in enhancing rucking comfort and pack stability. On both backpacks and tactical vests, the sternum strap securely attaches to ladder locks or tri-glides on the shoulder straps, allowing for precise adjustment to fit your chest level, ideally positioning it around armpit level or slightly below. Proper placement ensures that the pack remains centered and balanced, reducing strain on your shoulders and upper body during extended rucking sessions.

How Does a Sternum Strap Enhance Rucking Comfort and Safety?

Using a sternum strap while rucking offers a multitude of benefits that enhance both comfort and safety during your expeditions:

• Transfers Weight from Shoulders to Chest: The sternum strap effectively distributes pack weight more evenly across the upper body, significantly reducing stress on your shoulders and preventing shoulder fatigue during long rucks.

• Improves Posture: By keeping the shoulders back and the head up, the sternum strap helps you maintain good posture, preventing you from slouching forward under the weight of a heavy pack. This not only reduces back strain but also enhances overall balance.

• Stabilizes the Load: The sternum strap anchors the pack, minimizing side-to-side shifting during dynamic movements. This stabilization provides greater control over your pack, allowing for smoother navigation through varied terrains.

• Provides Extra Security: When the sternum strap is fastened, the pack remains centered on your back, and the shoulder straps are less likely to slip down your arms, ensuring that your gear stays securely in place.

• Facilitates Use of Trekking Poles: With the sternum strap offering additional stability, you can easily use trekking poles without the pack pulling you backward or interfering with your arm movements, thereby reducing lower body strain.

• Enhances Breathing Control: A secured sternum strap allows for better chest expansion, enabling you to manage your breathing more effectively, especially when carrying a heavy pack over long distances.

• Allows Arm Resting: By transferring some of the pack's weight to your chest, the sternum strap enables you to rest your arms on the shoulder straps, reducing arm fatigue and enhancing endurance.

• Keeps Hydration Hose in Place: Routing your hydration hose through the sternum strap ensures it remains stable and readily accessible, allowing you to stay hydrated without fumbling for your water source.

How to Use a Sternum Strap Correctly

Using your sternum strap properly is key to getting the most out of it. Here are some tips:

• Position it at the right height - As mentioned earlier, the ideal sternum strap height is around armpit level. Adjust it to sit comfortably without restricting breathing.

• Keep it snug, but not too tight - The strap should be tightened enough to take pressure off your shoulders, but not so tight that it's uncomfortable. About a two-finger-width gap between the strap and chest is ideal.

• Use it in conjunction with a hip belt - Make sure to always fasten your hip belt first when putting on your pack. The hip belt should carry most of the weight on your hips. The sternum strap is there for extra support, not to hold up the pack weight alone.

• Try using it only when needed - If you don't have a heavy load, you may not need the sternum strap all the time. Release it anytime you want your shoulders to bear more weight.

• Watch strap placement when using trekking poles - When using poles, position the strap so it doesn't interfere with your arm motion. You want the full range of movement.

• Remember to unfasten before taking the pack off - Releasing the sternum strap makes it easier to get your pack off without the strap getting caught on your body. Unclip it right before doffing your pack.

• Inspect it periodically - Check the sternum strap for wear and damage periodically. Make sure the adjustment buckle is functioning properly. Replace if needed.

Sternum Strap Benefits for Different Rucking Scenarios

The benefits of using a sternum strap vary somewhat depending on the type of rucking activity. Here's a look at how it can help in different scenarios:

Fitness Rucking

For ruck marching to build strength and endurance, the sternum strap helps in several ways:

• Keeps pack from bouncing during fast marches

• Lets you maintain proper posture on long hauls

• Makes it easier to use trekking poles for added upper body workout

• Helps expand the chest fully to get deep breaths when winded

Tactical/Military Rucking

Sternum straps are practically mandatory for tactical rucking with heavy loads. Benefits include:

• Keeps pack secure during dynamic activities like sprinting or crawling

• Provides stability for using a rifle while moving

• Let tactical vest sit properly when worn over the pack

• Helps keep the hydration hose in place for quick access

Hiking/Trekking

On long treks over rough terrain, the sternum strap:

• Stabilizes pack when climbing over obstacles or scrambling

• Offers extra security when leaning forward on steep ascents

• Helps keep the pack centered during side-hill traverses

• Makes it easier to grab gear like water bottles from the pack

Ultralight Rucking

Even with a light pack, the sternum strap helps:

• Takes pressure off shoulders when carrying pack long distances

• Prevents pack bounce during high-mileage hikes

• Provides stability when moving fast over uneven ground

• Lets you keep your arms relaxed at your sides to reduce fatigue

Rucking for Travel

Whether exploring cities or the countryside, the sternum strap:

• Keeps pack secure when navigating crowded areas

• Reduces shoulder fatigue from carrying packs all day

• Stops pack shifting when bending down to grab gear

• Provides quick access to valuables stored in the pack

Rucking with Heavy Armor

Rucking in heavy body armor like plate carriers places greater demands on your upper body. The sternum strap helps:

• Transfers the substantial weight off your shoulders

• Keeps armor riding properly when running or doing patrol movements

• Lets you move freely without restricting arm motion

• Makes it easier to shoulder a rifle while wearing a plate carrier

Potential Drawbacks of Sternum Straps

While sternum straps offer many benefits, there are a few potential drawbacks to consider:

• Can create pressure points or chafing on the chest when tightened too much

• May interfere with arm motion if positioned poorly

• Can catch on clothing or gear when taking the pack on and off

• Provides minimal benefit with very light packs

• Adds an additional buckle and strap to fiddle with when donning/doffing pack

• One more thing to break or fail in the field

Despite these minor disadvantages, most ruckers find the benefits of a sternum strap far outweigh any potential downsides. The strap is an inexpensive way to make carrying a heavy pack much more comfortable and secure.

Selecting the Right Sternum Strap: Key Features to Consider for Optimal Rucking Performance

Choosing the right sternum strap is essential to maximize the benefits and ensure comfort during rucking. Not all sternum straps are created equal, and selecting one that meets your specific needs can significantly enhance your rucking experience. Here are the key features to consider when choosing a sternum strap:

• Durability: Opt for a sturdy strap crafted from high-quality nylon or polyester webbing. These materials offer resilience against wear and tear, ensuring the strap withstands the demands of prolonged rucking. Avoid flimsy elastic materials that may stretch out or wear down quickly.

• Adjustability: A wide adjustment range is crucial for customizing the fit to your body shape. Straps with sliders and tri-glides provide greater flexibility and ease of adjustment compared to ladder locks, allowing for a snug and secure fit.

• Width: A wider strap (between 1.5 to 2 inches) is preferable as it distributes pressure more evenly across the chest, reducing the likelihood of digging or chafing. Narrow straps can create pressure points, leading to discomfort during long rucks.

• Padding: Some sternum straps feature padded or cushioned sections that provide extra comfort against the chest. Padded straps help absorb impact and minimize irritation, enhancing overall rucking comfort.

• Attachment Style: Ensure that the sternum strap easily attaches and secures to your pack’s shoulder straps. Compatibility with your backpack’s attachment points, such as ladder locks or tri-glides, is essential for seamless integration and secure fit.

• Extras: Additional features can enhance functionality and comfort. Look for reflective threading for increased visibility in low-light conditions, elastic sections that allow for stretch, and hose management loops that keep your hydration system organized and accessible.

• Cost: Sternum straps are available in a wide price range, but affordable options often perform well. Invest in a quality strap that fits within your budget while meeting the essential criteria for durability and comfort.

Popular Brands: Many pack manufacturers offer replacement sternum straps designed specifically for their backpacks. Additionally, universal straps from tactical brands such as Spec Ops, Mystery Ranch, and Eagle Industries are renowned for their quality and reliability, making them excellent choices for ruckers seeking high-performance straps.

DIY Sternum Strap Solutions

If you don't want to buy a new sternum strap, there are some DIY solutions:

• Use paracord or 1-inch nylon webbing threaded through shoulder strap ladder locks.

• Secure webbing or cord together across the chest with a buckle.

• Repurpose an old daypack waist belt as a chest strap.

• Use the sternum strap from an old pack on your new one.

While improvised straps work, manufactured straps hold up better long-term. A purpose-designed sternum strap is an inexpensive insurance to protect your shoulders and enhance your rucking experience.

Can the Sternum Strap replace the Hip Belt?

While the sternum strap provides helpful additional support, it cannot replace the role of the hip belt for bearing pack weight during rucking activities. The hips and legs contain the biggest muscles in the body, ideal for carrying heavy loads over a distance. The hip belt transfers the bulk of the pack weight onto these larger muscle groups, rather than heavily loading the shoulders and back. While the sternum strap helps stabilize the pack and take some pressure off the shoulders, it does not have nearly the weight-bearing capacity of a well-fitted hip belt. For heavy rucking, the hip belt remains an essential piece of gear that significantly improves comfort and efficiency. The sternum strap complements the hip belt nicely but does not negate the need for it. Ruckers should be sure to always use both the hip belt and sternum strap together to optimize distribution of weight and get the most out of their gear. For more information about hip belts, don't miss our previous article where we discuss whether a hip belt is really necessary for rucking.

In Closing

the humble sternum strap offers many benefits for rucking comfort, posture, pack stability, and security. While not mandatory, it's a worthwhile accessory that most ruckers can benefit from, whether marching for fitness or tackling tough terrain under load. Take care to position and adjust your sternum strap correctly for maximum effectiveness. Your shoulders will thank you over miles of marching with weight on your back.