Four years ago 39 year old rower Mark Obeney weighed 25 stone and was struggling with his weight due to lack of exercise following a serious car accident. He was left with multiple leg fractures and had limited mobility making it difficult for him to exercise, especially as he even found walking very painful.Following extensive treatment at Addenbroookes Hospital in Cambridge Mark had his last operation to remove the pins, plates and screws from his legs in 2002. His doctor gave him the go ahead to start light exercise and in a bid to get his fitness levels back up again he began using the Concept 2 Indoor Rower.Mark had owned an Indoor Rower since the early 1990s when he was a member of Broxbourne Rowing Club in Hertfordshire so he already knew the benefits of the machine. Under strict medical supervision Mark began using the machine for five or 10 minutes a day and didn't feel any pain. A year later and Mark was really beginning to feel the benefits of exercising again. He felt brave enough to join the Carrefour Health Club in Norwich where he set up a training programme with personal trainer Hayley McIvor. Taking into consideration Mark's improving but still limited fitness, he began a training programme of free and fixed weights alongside workouts on the Concept 2.After the car accident my Concept 2 got put away to gather dust in the cupboard as I was in too much pain to even walk let alone row, explained Mark.Once the final operation was out of the way though, I was really keen to get back on the machine again. I dusted it down and moved it into the dining room where I could use it every day. Training at home, and then joining the gym, has made such a difference and to date I've lost six stone and am continuing to do so.Mark has steadily lost around one pound per week and today weighs just 18 stone 13 pounds. Although he's found the last few months pretty tough, he's still training and aims to get down to 16 stone. That would result in a total loss of more than nine stone. My weight loss has recently hit a plateau but I've noticed that my clothes are fitting better than ever and in some cases are getting loose. It's not just about the scales though, it's about inch loss too!Nowadays my weekly routine is using the Concept 2 for 30 minutes or an hour each day supplemented with light weights and swimming. I'm entering the British Indoor Rowing Championships this year, I'd also like to total two million metres on the machine and row a marathon – on and off the water!I'm hugely competitive, I've got to keep going and beat my previous time!