LONG gone are the days when exercising meant going for a jog or heading to the local aerobics class.

These things still exist of course, but not quite in the same way - aerobics now means a long list of pump-it/dance-it/blast-it/shake-it-to-the-beat variations, there are all sorts of fancy gizmos and disciplines for strengthening up and, while jogging might still essentially be the same, look at how many people are now 'training' for an event, monitoring progress on smartphones and investing in the latest gravity-defying trainers.

Certainly, we're spoilt for choice these days when it comes to how we exercise. 2014 saw high-intensity interval training [HIIT] become mainstream, 'personal bests' are something everybody - not just pro athletes - think about, and getting-my-sweat-on overtook pouting-on-a-night-out as the social media selfie of choice.

According to the trend forecasters, there's more to come in 2015.

"We've all become more serious about sports and recognised that we might actually improve our performance if we trained specifically for the event," says leading personal trainer Matt Roberts. "It's taken a while, but following advice experts have given for years is now on-trend and set to continue. Blame/thank the rise of triathlon and cycling, and their physical and technical demands..."

Indeed, 'fit not thin' was the mantra for 2014, with toned, healthy and strong overtaking catwalk-skinny as the most bandied body ideal (hurrah!). But how we look isn't the only fitness reward we cherish; how it makes us feel is important too.

"Working out now isn't just for the sake of it, and it's not just for aesthetics," adds Roberts. "A trek, mountain climb, triathlon, duathlon or any of the other events available are becoming the norm. Find a new goal, make it big, the world is your oyster and nothing is going to stop you in 2015!"

Personal fulfilment, improved mental and physical health, camaraderie and supporting charity campaigns all feature on our list of motivations for pursuing challenges too. On a day-to-day scale, against a backdrop of obesity epidemic headlines and rising rates of stress and depression, each and every one of us can benefit from being active.

Here's a snapshot of the fitness vibe predicted for the year ahead...

TIME AND CONVENIENCE TOP THE LIST

"We're increasingly time poor," says Dave Kyle, head trainer for Les Mills UK. "We're working longer hours than ever, so finding time to work out can be increasingly difficult."

So as time is at a premium, the industry's catering to our needs by increasing short yet effective workouts.

"A huge trend for 2015 will be convenience and time efficiency," adds Kyle. "Whereas previous years we've heard about extreme and tough workouts, 2015 will see more classes and workouts being offered that fit in and complement our busy lifestyles.

"HIIT isn't brand-new but it's certainly a trend that will continue and grow in 2015. HIIT classes like Les Mills GRIT are typically 30 minutes and the feedback we've had is phenomenal. Participants love the fast and furious approach, and the fact it delivers results and fits into their schedule."

ANY TIME, ANY PLACE

Fancy pumping iron at 2am? Hitting that treadmill at midnight? No problem - it's getting easier to work out around the clock, and PureGym, the UK's leading 24/7 gym, now sees 20% of its members training at night, so those working shifts, for instance, can still benefit.

Despite the common advise not to exercise too closely to bedtime, PureGym general manager Lee Greenall says some people might find nocturnal workouts helpful: "A lot of people complain about not being able to sleep at night; this is because people store too much energy at the end of a normal working day. Their eyes might feel heavy, but their body is ready to release more energy.

"If you listen to your body, it will make you feel a lot happier and replenished, helping you to close down and sleep better."

Les Mills are also predicting their VIRTUAL workouts - where classes are played on screens - will be big in 2015. Eliminating the need to turn up at a prescribed time, virtual classes can be accessed any time.

LET'S GET FUNCTIONAL

In 2014, you might well have found yourself scuttling across the floor like a lobster or leaping around like an ape - primal movement-based exercise might sound like child's play but it sure does burn up those quads!

In 2015, the trend's set to develop further, with functional training putting a big emphasis on widening our range of movement and offsetting the damage of sedentary lifestyles.

"Functional training is a term that describes training the body in the way it was designed to move, and also to make exercise support an individual's goals," says Gillian Reeves, national group exercise manager at Virgin Active. "A lot of our movement these days is in the sagittal plane, movement that goes forwards and back, like walking, cycling, sitting at a desk. Our joints are designed to move three-dimensionally, but we typically put our bodies into positions that are sitting down with flexed hips and internally-rotated and rounded shoulders. Doing this without including any functional exercise into your week can give you movement dysfunctions and injuries over time, and will reduce your range as you age."

In 2015, Virgin Active will focus not only on getting us moving more, but 'working up a sweat with a purpose'. The Grid, their exciting new addition, will see us "being more mindful of our movement and recovery", says Andy Birch, the brand's head of exercise and wellbeing.

In four formats - Lean, Fit, Strong and Active - the classes are an evolution of the HIIT/crossfit/circuits philosophy, incorporating numerous apparatus and engaging the whole body. "Grid classes are the ultimate in 30-minute tough workouts," adds Birch.

STRONGER THAN YESTERDAY

More women than ever have started including weight training into their fitness regime; could our 'I'll look like a bodybuilder' fears finally be gone for good? A beautifully honed bicep and sculpted quads are now the most envied curves in town, it seems, and industry insiders certainly think more and more of us will be muscling in on this trend in 2015, with old-school equipment like gymnast rings, for pull-ups and dips, and monkey bars a key feature for Fitness First. They're also predicting their Freestyle Strength Training class and FGT (freestyle group training) HIIT class to be popular.

* Variety - forget sticking to one or two forms of exercise. The choice of classes and facilities has never been so vast and people are cottoning on; mixing it up keeps things interesting and means a more over-arching workout.

* Doing it for the kids - more focus will be put on catering for youngsters and families. Les Mills recently launched BORN TO MOVE classes, catering for 2-16-year-olds, which are set to reach more locations in 2015.

* Channel your inner athlete - with London 2012's legacy still going strong and more of us signing up for challenges, you'll find plenty of ways to train like the pros. Fitness First have developed a Team GB Pro Athlete programme to give members a taste of training, Olympian style.

* Outdoor training - getting outdoors to exercise means vitamin D top-ups, fresh air in your lungs and an extra sharp endorphin rush if it's cool, plus best of all, if you simply don a pair of trainers, it's entirely free.

* Make a splash - swimming's the UK's most popular sport, in terms of participation, with around 2.9 million of us taking a dip at least once a week. It's a fantastic, low-impact, whole-body workout and even more of us are expected to take the plunge in 2015.

* Tech me as I am - apps, gizmos and gadgets galore now play a key role in our fitness habits, and in 2015, it looks likely that tech will continue to help us monitor progress and smash those goals.

* Regeneration - a growing buzzword, that token 60-second warm-down won't cut it in 2015; anybody worth their moisture-wicking threads knows that helping those muscles heal is just as vital as how many reps you managed. What do you mean you don't own a foam-roller yet?!