The 52-year-old from Dumbarton is a porter at Gartnavel Hospital and was inspired to get active by the NHS Greater Glasgow and Clyde Cycle to Work Scheme, which gave him the means to buy a new bike, and he says it has made him a new man.
Less than six months later he had shed four stone, cycles 10 miles every day without breaking a sweat and every week he now eads for the fresh fruit and veg aisle rather than the sweeties.
"I wish I'd made these changes sooner," he smiles.
"After I got the bike I thought I was 18 again and quickly realised I wasn't after pushing myself too hard to fast.
"I went back to basics and started cycling a mile a day, then two, then five, gradually building up my fitness and resilience.
"That was in August and as soon as the weather improves I'll be cycling into work every day, which is 12 miles each way."
Robert says he feels so much better, has more energy and sleeps better at nights, since he started cycling. Pain from arthritis in his legs has also eased because he is carrying around less weight.
His partner Rona started a pedometer step challenge at the same time and has lost nearly two stones.
After starting regular exercise Robert very quickly found he wanted to eat more healthily. He changed his diet, swapping crisps and fizzy drinks for healthy foods and snacks.
"For years I ate pretty unhealthily," he admits. "My first port of call when doing the food shop was to head for the goodies aisles and then think later about what more healthy items I needed. That's all changed. I'm straight into the fruit and veg section now and it's all so much tastier than the stuff I used to buy."
At first Robert says his transformation and weight loss was more apparent to others than himself.
It was when he was going on holiday with his partner Rona in November that it really hit home.
"We were standing at the check-in desk and I loaded our suitcase onto the conveyor belt to be weighed.
"We all know the stress of trying to keep to the luggage weight limit when flying so I was relieved when the screen showed it was 19kg, just under our 20kg limit.
"My next thought, looking at what was a rather large and bulging case, was that it I actually had lost 1lb more in weight than the case. I just couldn't get my head around the fact that for all these years I had been lugging around the same amount of weight in excess fat as the suitcase in front of me.
"It was then I realised just how much I'd actually lost and it felt fantastic."
Robert is backing the NHSGGC Active Staff campaign, which is launched today and which encourages employees of all ages to take that first step to increase activity levels.
"I can't believe how taking that first step and buying a bike though the cycle-to-work scheme has changed my life. It really was just that, a small step to see if I could get into cycling after so many years and it turned out to be the best thing I've ever done."
Robert is one of hundreds of health board staff who are reaping the health and financial benefits of signing up for the scheme which offers the opportunity to buy a bike at a reduced rate and make the payments through a salary sacrifice tax reduction.
The cycle initiative, which is run jointly by the Department for Transport and HM Revenue and Customs, is designed to encourage staff to choose an active form of transport to get to work and has been so successful that NHSGGC is the only health board to be included in the national Cycle to Work top 10.
Our Active 2014 campaign, with partners Glasgow Life and NHS Greater Glasgow and Clyde, is targeted at improving the health of Glaswegians in the year of the Commonwealth Games and building a lasting legacy of physical wellbeing.
Focusing on events and individuals of all ages, we aim to improve the health of as many people as possible in the community.
The positive message of this campaign is that even the smallest of changes in activity and lifestyle can make a huge improvement in health.
We will target a series of health goals, including basic fitness, obesity, diet and smoking cessation.
We want to do all this by raising the profile of health and fitness initiatives and opportunities and to show that you don't have to run marathons or pump iron to transform your life.