It is also the time to get injured. After months of heavy training, many people want to sprint outside on the first flower filled day and snap. Yes, all that heavy training led to wonderful improvements in muscles mass. The extra layers of body fat, to keep a cold lifter warm, also change the dynamics of movement. The extra strength and size are wonderful, except that the body needs a few days to adapt before all out sprinting.
Spring is time for Transformation programs.
Let the reps increase in the gym, but start to measure rest time. Add some movements that mimic outdoor activities. Traditionally, calisthenics have been used to prepare athletes for movement. The old dictum of If you want to run fast, you have to train fast certainly remains true. As the world begins heating up, it is also easier to get lean.