From a health & fitness perspective, pretty much everything!!
Due to the compact and ergonomic shape of kettlebells, you’re able to develop strength and conditioning in a variety of areas in your body simultaneously whilst developing fundamental benefits to your overall health and well-being. The easy handling of kettlebells also allows you work with lighter weight for longer periods of time, developing a greater cardiovascular system.
In a world where many people spend a substantial amount of time either in front of a computer, behind a steering wheel, watching TV or looking down at a phone, good posture through core and posterior chain strength and stability has never been so important to actively improve and maintain.
This is where kettlebells really shine over other forms of exercise equipment due to their compact, hand-held structure. For many of the more popular kettlebell exercises (swing, snatch, press, clean, squat), you're fundamentally required to keep your shoulders back, lats engaged, and core braced in order to maintain good posture throughout the exercise, otherwise you'll likely experience continuous flexion and extension throughout the spine, resulting in back pain and less engagement with the muscles you actually should be using. Maintaining good posture throughout workouts with weight in your hands will no doubt improve your overall core and posterior chain strength, mobility and stability in everyday life, making kettlebells an excellent tool to enhance your long-term physical health.
Grip and nerve strength has also taken a back seat due to decreasing manual labour in day-to-day life for most people compared to years before, and even when exercising, belts and wraps are used to allow people to lift weights that their grip and posterior chain can’t handle.
Grip strength will hugely benefit from the vast majority of kettlebell exercises which are handheld. Due to its shape, the overall weight of a kettlebell is not evenly distributed as its centre of mass is extended beyond the handle. This is also highly functional too when you compare it to carrying shopping bags where the centre of mass is also further from the handle. Grip strength is something that's often overlooked until later years when it's too late and causing a loss of independence, despite being hugely beneficial throughout life, especially from a resistance training standpoint.
Pictured below are the fantastic Cast Iron Kettlebells from Iron Foundry Weights which I use both for PT sessions with my clients as well as my own training. Their design and shape allows for free flowing movement during ballistic exercises and they even have rivets in the horn in case you would like to add greater concentric and eccentric resistance using bands (also pictured below). Check out their full range of sizes at www.ironfoundryweights.co.uk