Variety is the most important variable in your workout routine. If you are not seeing results it’s probably not just due to lack of intensity, but instead lack of variety. If you do the same thing everyday, you can expect the same result. If you do different workouts and challenge your body in different ways, then your body will respond differently. Fairly common sense but I think we all tend to forget about how easy it is to get caught up in comfortable.
The human body is meant to move and the moment that all we challenge it with is the same movement then it gives up with progression. We must constantly change things up. As simple as time, intensity and weight. All things in moderation is key. Clearly if you are training for a century bike ride, you will be spending more time on the bike, however, you need to supplement with resistance training and other forms of cardio training to ensure you are most efficient while on the bike. Even if you are not training and your goals are that of weight loss or general fitness the same holds true. You must add variety. Maybe one day you take a TRX class, than the next a cycling class then the third day a bootcamp class and end your week with a Yoga class. The point is the body is always being challenged in different ways. More importantly your mind is kept from getting bored and you stay consistent and inspired with your workouts.
I could go on an on with how you can add variety to your workouts but the best recommendations is to try new things. Who knows, you may find that you love ice skating or swimming or that rock climbing is your new-found strength training activity.
Whatever it is, always seek out more and I promise you will never get bored of working out and seeing results.