'I took my fly-and-flop family to a relentless resort with 36C beach workouts'

Feeling like an 80-year-old, clambering over slippery rocks on all fours, I appear to have acquired my own personal hand-holder. George – one of the tour guides from Climb Up Outdoor Activities – is helping us hike through water ponds, vegetation and “picturesque” (read: broken) wooden bridges, to the Polilimnio Waterfalls in southern Greece.

I’m not the oldest or least fit here, but I may be the most clumsy. The “easy” hike, suitable for children, is only a mile, but the polished limestone and tricky terrain can be challenging.

We spot waddling crabs and scarpering lizards as we climb, finally arriving at the hidden freshwater lake and waterfall. I’m here with my family – husband James and kids, Rosie, 15, and Poppy, 12, on an excursion from Neilson’s Messini Beach Club – a 25-minute drive away, near Kalamata on the Peloponnese peninsula.

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We strip off and make our way into the 16C water, James diving off boulders with confidence, Poppy cannonballing into the lake, Rosie nervously jumping, while I slide in. The water streams down the rock face, shushing all thoughts from our minds. And boulders bulge, providing diving platforms, and ledges for bushy green Daphne trees.

As summer holidays go, we like the fly-and-flop set-up. Family life is so hectic that when we have a week in the sun, we prefer to do very little. But here we spend the first couple of days setting alarms for all the activities we’ve booked.

Neilson is renowned for its activities, and you can try your hand at almost every watersport, racket game and fitness class while you’re here – all included in the price.

We’re not an especially fit and active family – we all do a bit, but more for mental health benefits, or to balance out our food and drink indulgences. I seem to get injured every time I go at anything with great gusto these days, so I’m a low-impact lover, but while we’re here, and it’s free, I’ll have a go.

I wouldn’t have predicted fancying a 4pm Pilates class in 36C heat, but with sore quads from yesterday’s “workout of the day” and a window of time following a late lunch, here I am. It takes place on a shady sun deck overlooking the ocean, where sailboats are lined up on the sand.

We stretch it out for 45minutes, poses gradually getting more challenging, and then I head to the pool for some late afternoon lounging. Another morning, we sleep through our 9.30am “intro to pickleball” slot, but the courts, smaller than tennis ones, have boards up displaying rules, so we grab our paddles and play.

Doing AMRAP (as many reps as possible) in a warm studio is a challenge, but as James and I make our way through press-ups, weighted sit-ups, squats, lunges, box jumps, 100 yard rows and burpees, pretending not to compete with one another, it feels good to do a proper workout. Twenty solid minutes is all it takes to kill us off, and we waddle away with jelly legs, drenching ourselves in water.

Aqua is also fun here, with good music and a decent pace making it more of a workout than the old-lady bobbing we’re used to at home. But it’s on the beach where you really get your value for money.

We rise early and head down to the sea, where a steady stream of people are enjoying their pre-booked slots. James, having waterskied 30 years ago (ahem), opts for skis, while the girls try a kneeboard for beginners. Laying on their bellies, once the boat gets some speed up, they can spread their arms out like pelican wings and skim across the sea like a pebble.

Mastering the art in no time, Rosie hauls herself up to her knees, riding the board with no hands. You can still fall off, but it’s sturdier and less about technique, so is a good way to start out.

Listening to my kids sing Mr Brightside in the sea, as they alternate between paddleboarding pros and faceplanting failures, fills my heart with joy. I sit smugly on my sun lounger, watching triangular sails glint in the midday sun.

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Families try their hand at windsurfing, cores braced as the sail sends them off balance and gravity plonks them into the sea. The undulating peaks of the Taygetus Mountains stand proud and pensive in the background.

The landscape is typically Greek – thirsty grounds, parched grasses sprouting from the sand. Even cacti look like they need hosing down.

Giant ants scurry along the stony sands, busying themselves like tourists, while I take a minute to have a breather. The food here is good. We’re not usually fans of buffet-style all-inclusives, but there are specials available at every meal, with plenty of salads, meats, veggies and child-friendly options.

Staying for seven nights, we’re entitled to all breakfasts, lunches and four dinners. On the other three nights, they offer different menus (£9.75 per main) and a barbecue night with live music (£21pp).

Alternatively, you can wander further down the beach to traditional Greek tavernas, where a family meal costs us £70. Or ride a bike one tiny kilometre to The Phoenix, where we buy bargain olive oil to take home, and sup on Aperol spritz (£7.60) and Coke Zeros (£2.10). If you’re feeling really flush, you can splash out on a £25 cab and head into Kalamata, which has a quaint old town, plenty of shops, and great restaurants.

“One two, one two,” Rosie and I chant, as we attempt to paddle our oars in unison. We’re sitting in a bright orange kayak heading for a local beach bar for a swim and a coffee, but we seem worse team rowers than we are solo. We study everyone else and adjust our oars accordingly, perhaps improving slightly, but it’s probably the direction of the wind giving us a helping hand.

We row around older Greek folk, chatting while they tread water, and head back to the pool bar for our pre-dinner ritual. Parasols are lined up like cocktail umbrellas, and we order mojitos, pina coladas and mocktails.

As I’m getting ready for the evening, my arms feel like they’re shaking intensely. Today, I introduced my 6ft 2in former rugby-playing husband to the joys of Boxfit. And it turns out, he has a right cross Tyson Fury would be proud of.

The fitness provision here is brilliant – something they’ve invested in over the past year. And every day, one of us is full of intention for something new. After mastering the paddleboard, James declares he’s going to do it every day.

When the pool clears for lunchtime and Poppy finds some space to actually swim, she decides she’s going to smash out 20 lengths a day, and inspired by AMRAP, I talk the girls into devising a daily session once we get home in an attempt to do a bit more cardio.

For a family that generally likes to do very little on holiday, I’m pleasantly surprised to find we all have a fondness for fitness. And all that hard work means I can slurp another mojito.

Book the holiday

• Neilson offers seven nights on club board at the Messini Beach Club near Kalamata, Peloponnese, Greece, from £1,467pp based on a family of four sharing and departing from Stansted on August 24. Includes transfers, kids’ clubs, activities, and expert tuition. Birmingham and Manchester flights also available. neilson.co.uk
• More info at visitgreece.gr