Many of us will have experienced 'social jetlag'- that jaded feeling upon returning to work following the Christmas break. Late nights and long lie-ins can make it difficult to get back to our usual routine, and while our body clocks can take a while to return to normal it's common for us to feel a little sluggish as a result.
This, combined with any 'return to work blues' can make finding the motivation to exercise particularly difficult - no matter how high it is on the list of New Year's resolutions.
The good news is that as well as helping to lose any excess weight gained over the festive period, increasing activity levels can also boost your energy levels, which will in turn make it easier to stick to your exercise regime - a virtuous circle.
Taking regular exercise will also help to strengthen your immune system - reducing your chances of winter infections, helping you to feel emotionally positive and improving your general sense of wellbeing.
Adults should do at least 30 minutes of moderate-intensity aerobic exercise (such as brisk walking or cycling) at least five days a week.
Moderate-intensity exercise should slightly increase your heart rate, make you feel warm and you may even sweat a little. You should be able to talk, but find singing a song difficult at this level of intensity.
Along with moderate-intensity activity, it's also recommended that adults carry out some muscle-strengthening exercises such as working with weights, body-weight exercises or yoga at least twice a week and that we minimise the time we spend sitting down.
Top tips for keeping active:
• Although joining a gym isn't necessary to get into shape, many gyms will have deals at this time of year. You might be able to find one that includes sessions with a personal trainer, which will help you figure out realistic goals and keep you motivated to achieve them
• Find activities you enjoy that can fit into your routine
• Exercising with a friend might help your motivation to stick at it
• Always warm up before you start exercising
• Start slowly and build up graduall
• Stay warm if you are exercising outside - it's a good idea to layer your clothing and wear a hat if it's very cold
• Invest in some reflective clothing for the dark winter nights and mornings
• Stay hydrated - drink water little and often before, during and after exercise
• Every little change will help, so walk at least part of the way to work or use the stairs rather than the lift. Even digging the garden, raking the leaves and hand-washing your car instead of going to the car wash will help you improve and maintain physical fitness
• If you haven't already, consider checking with your GP if you have any conditions or injuries that may be worsened by exercise or may limit your ability to exercise.
Remember - listen to your body. Minor aches and niggles are common and normal during exercise but if you start to feel a significant increase in your discomfort then stop immediately and rest for a while. If you feel recovered and able to carry on then gently give it another go - but if you start to feel uncomfortable again then you should probably call it a day.
If you're worried or if the discomfort persists then consider talking it through with your doctor or call the NHS helpline on 111 for advice.