The summer starts with the best intentions. As bikini time approaches, you may have organised a ferocious workout at the gym. You may have even done it a couple of times. Then, all too quickly, the holidays are here and you’re going away for a week or two. What’s going to happen to your fitness routine? Will you find a gym where you are on holiday? Not likely.

However, abandoning your new regimen could be a disaster, ruining everything you have achieved and encouraging you to give up for the rest of the year. Exercise routines are hard to establish and easy to let slip. I’ve taken up, and abandoned, at least 30.

And so, when I was due to go on a trip across the American West in a 30ft “RV” (aka recreation vehicle or motor-home), I was worried. I’d only just signed up with Srbo, a fab personal trainer at my gym in London. Plus, can you imagine a more cellulite-friendly holiday than a road trip in America? And so I entreated Srbo to devise a purpose-built holiday routine for me. Or, as he called it, a “trailer-trash workout”. It’s adaptable to any holiday venue and for anyone in “holiday-mentality” mode.

You don’t need any special equipment. All you need for this workout is a pair of trainers and a pair of large plastic bottles: 2l (3pt) or thereabouts. I picked up a pair from Wal-Mart and filled them with water. These were my weights.

The second holiday workout bonus is that it is not too taxing. If it looks like a scary 60-minute experience, you will never do it. This one takes 20 minutes, which if you are on leave with small children is about long enough to abandon your entire family to someone else.

“Always do it after breakfast, before you set off for the day,” ordered Srbo. So I did. Throughout the trip. In a carpark at Death Valley, on the Las Vegas Strip, on the high desert plains of Arizona and even at the Grand Canyon, at an altitude of 8,000ft. Most bracing.

STEP-UPS

The workout begins with a two-minute stint of step-ups, which I did up and down the steps of the RV. Torture, but two minutes isn’t long and I always think it’s best to get the worst over at the beginning. This is followed by 30 squats.

WEIGHTS

After this it’s time for weightlifting with your bottles. First, you must do 20 lifts. Touch your toes with the bottles, with knees bent, and then, standing straight up, lift the bottles above your head and straighten your arms.

WALKING LUNGES

Walking lunges next: 15 lunges one way around the RV, 15 the other, carrying the weights. To do a walking lunge, step forward with your left leg and lower your right knee to just above the ground, then bring your right leg up and step forward to follow through with a second lunge. Squeeze your glutes as you walk. It’s killing you? It’s working.

ROWING

Stand with your feet apart, knees bent, hands down with weights. Pull the weights up to armpit level and then lower. Do this 20 times

STATIC LUNGES

Then do 30 static lunges, with one leg on a step (in my case of the RV), 15 each leg. Instead of walking forwards you return to the starting position and then swap legs. Was I embarrassed performing static lunges in a Death Valley car-park? Not really. A few people gawped, and one person yelled over that I was an “inspiration”, which was nice. You’ll never see the gawpers again anyway. Remember, you’re on holiday.

BICEP CURLS

After your static lunges, it’s time for bicep curls. Arms out in front at 45 degrees to your body, palms up, a bottle in each hand. Raise your hands to your shoulder and slowly lower to 45 degrees again, 20 times. Put the bottles away.

STEP DIPS

You’re on the home straight. Do 20 step dips, which I did on the steps of the RV. Sit with your back and bottom just skimming a step/firm base and put your legs out straight, place your hands on the edge of the step, move your bottom a couple of inches away from the step and lower your bottom as far as possible by bending your arms, then raise your body back up.

STOMACH WORK

Get a towel out and do 20 press-ups. Then roll over and suck your tummy in ten times, for ten

seconds at a time. Sit up with your back straight and your feet raised, hands outstretched, balancing on your bottom (see above). This is a great abs exercise. Count for a minute. I made a small child count for me, which meant that the torture seemed to go on for about half an hour.

SKIPPING

Finish with two sets of high skips around the RV, five times one way, and five times the other. Remember to keep your knees up, and swing those arms. This could be done around the living room of a ski chalet, a caravan, or anything fairly large. You should be breathless when you finish. And triumphant. I achieved my goal of six workouts, with the pleasing result that my body didn’t go into morbidly obese mode during my drive across the fast-food nation; nor did it collapse when I returned to my normal routine at home.

Break sweat

Do these on three consecutive days, then take a day off. Take only 30 seconds rest between exercises.

1 Two minutes of step-ups

2 30 squats, hands on head

3 20 clean-and-press, with weights

4 30 walking lunges, with weights

5 20 rows, with weights

6 15 static lunges per leg, with weights

7 20 bicep curls, with weights

8 20 step dips

9 20 press-ups

10 10 x 10-second belly vacuum

11 1min balance, back and legs off ground

12 2 x 5 high skips, one set each way

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