While the Tokyo 2020 will provide iconic moments, treasured memories and the fulfilment of lifelong goals for some British athletes, for others who will miss out on the Games due to injury or non-selection, the summer months will prove challenging.Swimmer Jazz Carlin has first-hand experience of just that, when illness derailed her bid to qualify for London 2012. After watching that Games from the stands, she used the disappointment to spur herself on, earning selection for Rio four years later and coming home from Brazil with two silver medals, being beaten only by American great Katie Ledecky. Here, she shares her experience between 2012 and 2016, and gives advice for British athletes who may have faced selection disappointment this time around.June 2012:“I touched the wall and felt numb, empty, speechless with the realisation that the dream I had for many years had come crashing down right in front of me. After all the sacrifice and early mornings and hard work, tears fell down my face and I couldn’t look my coach in the eyes, feeling like I’d let him down and the dream we had made together was no longer in sight.“I tried and look for answers and reasons why it didn’t happen to me, but it is only looking back now that I realise how I wasn’t ready to take on the best in the world and perform to the best of my ability.” Post-London:“After a few months out of the water and the heartbreak of watching the Olympics, I decided to get my tonsils removed. They had caused me a lot of pain and discomfort, which had then interrupted my training. After a very sore operation I can now say it has been one of the best decisions I have made for my swimming career. “Starting the season off, I knew it was going to be tough getting back in the water after my longest time out of the pool since competing at national level, but I knew I had a hunger for success like never before.“I even felt revenge; I wanted to bounce back, I didn’t want to let something knock me back from something I loved and my dreams. My first session in the pool was incredibly tough, after having a long break every metre hurt and I felt like I wasn't moving. My arms were burning and felt like I had bricks tied round them, but I knew this was going to be the hardest part. The first few weeks were always going to be tough; my body had been resting for a few months and definitely got used to having a break!“Week by week I felt stronger in the water and could see improvement – my times were dropping and I felt like my body was slowly getting back into good shape. I took a very harsh attitude, not satisfied with my times in training and pushing harder each session. My attention had to quickly turn to the world Championships.”December 2012: “Worlds started off with a best time in the 400m but narrowly missing out on a bronze medal by 14 one hundredths of a second. I was gutted, holding my head in my hands and annoyed with myself but I gave it everything I had, I couldn't control what everyone else was going to do. “The rest of the week didn't go the way I had hoped for – two ninth places by the smallest margins, which meant I couldn't race in the final therefore out of the running for a chance at getting a medal. I was disappointed with myself as I knew I had done times fast enough to be in those finals but that week it wasn't meant to be. “I was not satisfied in making teams and going to big championships, I wanted to be fighting for medals and pushing myself as hard as I can. Even though I didn't achieve my goals of making the London 2012 Olympics, I still had a huge dream and desire of going to an Olympic Games.”2014: “I picked myself up and focussed on the Commonwealth Games, which were to be held in Glasgow. It felt like the home games that I never had, and I was more motivated than ever to perform at my best. I had a such a great block of training and was so excited to compete at the games.“My coach at the time then told me in April – three months before the Commonwealth Games – that he was relocating to Australia to live and coach over there. I was devastated; I had worked with him for seven years and it was so close to the Games. “I decided to carry on with the same programme up until the Games in the UK with no coach, as doing something new so close to the competition could have a detrimental effect on my performance. I had to turn up to training and sometimes I would be the only one in the pool, nobody was watching but I didn't want to let anything get in the way of my dream of winning gold in Glasgow. “I had so much emotion competing at the Commonwealth Games: all the upset and memories of not making a home Olympics and also competing without my coach – it was tough. “However, I came away with a gold and silver, and set a new championship record in the process. That will be a memory I will never forget.“Three weeks later, I then went on to compete at the European Championships in Berlin, coming away with two gold medals and again breaking the championship record. I finally felt like my dreams of competing at an Olympic Games were getting closer.2015:“My next international competition was the World Championships in Kazan, Russia. Again, in my first race, I was agonisingly touched into fourth place. This time I learnt from previous experiences and how to deal with the disappointment, as I had another race later in the week. I managed to stay focussed and come away with a bronze medal in the 800m freestyle.2016:“Coming into Olympic year, I couldn't have expected the overwhelming emotions I had going into the Olympic trials. I so desperately wanted to be on the Olympic team.“Unfortunately, six weeks before the Olympic trials I had to return early from a training camp in Australia, due to an injury on my rib that needed further treatment back home. This knocked my confidence and placed doubts in my mind, reminding me of all the upset from 2012.“Luckily, the great team I work with got me fit enough to compete at the Olympic trials, but my confidence was a bit dented, and I put a lot of pressure on myself. Due to all of this, I didn't perform as well as I had hoped in the Olympic trials but on my final swim, I achieved the qualifying standard to go to the Olympics.“It was very emotional and felt like a weight had been lifted off my shoulders after four years. This is when the excitement began…“Not having the worry of qualifying, I felt so much more relaxed in the pool and enjoyed my training so much more. I put a great block together leading into Rio and with the help of the amazing team I had around me I left the UK in the best shape I could be. “Standing on those blocks in Rio, I didn't feel the pressure, just excitement to compete with the best in the world and to give it my everything. “I did a best time in my first heat swim, and I knew from then I was ready to race. I stayed calm and made sure I recovered well for the final later that day.“In the final I swam another best time, which got me a silver medal. I can’t really remember much about the race, but when I touched the wall, I just felt so happy.“Later in the week, I managed to come away with another silver medal in the 800m freestyle. My dreams had come true, I had competed at the Olympics and stood on the podium – twice! It was so special and something I will never forget.“Even though I will always have the memories of missing out on London, I have made many more exciting memories.“After competing at various competitions along the years I have built up so much experience and even though it hasn't always gone the way I wanted it to, I wouldn't have changed anything. It's made me the athlete I am today, and I am so much stronger now than I have ever been.“I will never stop loving the feeling of being in the pool, racing and all the excitement I get around the big competitions. I don’t always love all the hard slog of training but when I get to the big competitions it makes it all worth it. I know that when I set my mind to something I will do absolutely anything to achieve it and most of all I can handle anything that gets thrown at me. “My advice for every athlete is to try and enjoy every minute. Sport gives you so many different opportunities: take what you can from every situation. Try and be kind to yourself and appreciate those small wins because when you look back at your career in sport, they will seem so much bigger!”The BAC offers independent, confidential support to its members. If you are in need of advice or guidance on any issue, email support@britisheliteathletes.org.