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By Fluid X

Why Aqua Bags are the Only Gear You Need for Functional Strength Training

Functional strength training: the latest buzz in the post-pandemic workout world. If you’re interested in getting started with this type of training, aqua bags are your best friends to spice up your workouts and reach your fitness goals.

But what is functional strength training exactly and how can it help you? 

From hauling groceries into your car to walking your dog, you’re using your functional strength: the ability to exert your joints (shoulders, hips, knees, and ankles) through a full range of motion without pain, stiffness, or restriction.

But sometimes, your knee gives out or you suddenly feel a sharp pain in your shoulder as you were putting the milk in the fridge. And that’s where functional strength training comes in. 

Functional strength training aims to improve your core strength and stability so you can perform everyday activities with greater ease and flexibility. 

Rather than working on one particular muscle or group of muscles like most bodybuilding exercises, functional exercises train several muscles and joints together in your body to improve movement as a whole – and your quality of life. 

Some examples of functional exercises include: 

  • Push-ups and pull-ups
  • Jumping jacks
  • Lunges
  • Shoulder press
  • Tricep extensions
  • Skaters
  • Russian twists

But does functional strength training actually work? Let’s find out. 

The science behind functional strength training

A man squatting down with FluidX's tank aqua bag over his shoulders - FluidX

One popular type of functional strength training is instability training which involves carrying out functional exercises in unstable conditions with body mass or external weights as resistance. Instability training is known to enhance workout performance, support rehabilitation, and promote musculoskeletal health. 

Research shows that instability training greatly improves physical rehabilitation and maximizes overall athlete performance, making it extremely beneficial for people of all ages at different levels of their fitness journey. 

Another study from Sports Health Journal also found that instability training even increased trunk muscle activation by an average of around 47.3 percent.

Several sports equipment have been invented to support instability training, such as Swiss balls, Bosu balls, round balance (wobble) boards, suspension trainers, and aqua bags.

A woman carrying FluidX's Boba aqua bag in her hands - FluidX

Although past research shows that using multiple instability devices may increase core muscle activity, using more equipment doesn’t mean more muscle activity. In other words, people only need one workout tool during their functional strength training sessions. 

To put this into perspective, a 2005 study revealed that while planks performed with your arms in suspension devices increased activity of both the abdominals and obliques, there was no difference when another suspension device was added to the feet. 

Take the Bosu ball, for example. Even though the dome-side down helps users incorporate multi-directional movements, the design for the flat portion down provides a rather immovable base and unstable top. 

A 2014 study also found that when people performed bodyweight sit-ups with the ball placed under their lower back (flat side down), there was little to no change in abdominal muscle activity. 

Similar findings were seen for the Swiss ball. Performing traditional exercises (like crunches, dumbbell chest press, shoulder press, or lateral raises) indicated no increase in abdominal activity compared to sitting on a flat bench. 

The best alternative to these equipment is the aqua bag, a fun and portable water-filled training bag that you can use for at home workouts or pack it into your bag. Find out the benefits of training your functional strength with aqua bags in the next section. 

How aqua bags build up your functional strength

A man carrying FluidX's Boba aqua bag over his shoulders

Similar to Bulgarian bags, an aqua bag is a water-filled training tool that can be used for a variety of exercises that involve lifting, running, jumping, climbing, squatting, lunging, and rowing movements. You can see how it fits in with functional strength training. 

Unlike traditional strength training with weights in the gym, the constantly shifting water in an aqua bag mimics the instability in sports like rugby, judo, and tennis. It also adds weight and a degree of instability that solid training tools can’t offer, making for a unique yet killer workout. 

Functional strength training with aqua bags helps build power, explosiveness, and strength conditioning for both your lower and upper body. The unstable motion of the water in aqua bags challenges your postural and joint stability right away. 

But the beauty is: a heavier weight doesn’t necessarily mean a more challenging workout. You’re already challenging your core and stability just by picking it up. 

A man squatting down with FluidX's Tank aqua bag in his hands - FluidX

With aqua bags, you can carry out various movements: forward and backward, side-to-side, and even diagonal, during which your smaller stabilizer muscles work harder to control posture and stabilize the entire body.

In addition, aqua bag training targets core stability. The constant flow of water demands strength and stability to balance the bag, intensifying your daily workout while reducing the risk of injury.  

Exercising with aqua bags also allows for a situation of unexpected force, where the body uses co-contractions and automatically contracts specific muscles to absorb the force. When you regularly train with this unexpected force, your muscles get stronger and you learn to stabilize your body better in everyday life. 

FluidX offers two different types of aqua bags: Tank and Boba that come in four different sizes and adjustable weights ranging from 0 to 20 kilograms when fully filled. You can easily adjust the weight by adjusting the water level. 

With FluidX’s aqua bags, you have complete control over the degree of instability. For instance, the less water you put in the bag, the easier the water can move and the more you’ll need to try to balance it. 

Whether you’re just getting started with functional training or you’re already a pro, the versatility of aqua bags can help you achieve your fitness goals, whatever they are. 

Break free from the monotony of gym machines and the same old regular workout routines with aqua bag functional strength training. 

You can learn more about our aqua bags at

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