Bodyweight training can be just as effective as a gym
There's a common belief that serious progress in strength and muscle size is impossible without free weights and machines, and that bodyweight training is only good for beginners maintaining basic fitness. The reality is more nuanced: progressive overload, the core principle behind muscle growth, is entirely achievable without external equipment — through harder exercise variations (from regular push-ups to one-arm push-ups, for instance), more reps, a slower tempo, or shorter rest between sets.
Studies comparing high-effort bodyweight training with traditional weighted strength training at comparable effort levels find similar gains in strength and muscle mass, especially within the range accessible to most untrained and moderately trained people. The real limitation shows up at an advanced level: a very strong athlete eventually finds it harder to locate bodyweight variations difficult enough to keep progressing — external weight offers a more convenient and predictable way to linearly increase load at that point.
Practical takeaway: for most of the training journey — from beginner to advanced hobbyist — lack of gym access isn't a real barrier to gaining strength and muscle, as long as bodyweight training is approached just as systematically as training with weights.