The short answer
No. Building a lot of muscle takes years of focused training and eating in a surplus; it does not happen by accident. Women gain muscle at a similar relative rate to men, but start from a smaller base with much less testosterone, so the absolute gains are smaller. Lifting heavy mainly makes you stronger.
Why it does not happen by accident
Muscle grows slowly, often well under a kilo a month even for beginners. Very muscular physiques are the result of years of work, eating to gain weight and deliberate choices.
What the research says
A 2020 meta-analysis by Roberts, Nuckols and Krieger found that women and men gain muscle at similar relative rates, and that women gain upper-body strength even faster in relative terms. Absolute muscle gains remain smaller in women.
Heavy or light?
Heavy loads (6 to 10 reps) and lighter loads (15 to 20 reps) build similar amounts of muscle when the sets are taken close to failure. Heavy loads build more strength. Neither is more feminine.
The “toned” look
Looking toned means having some muscle and not too much fat over it. It comes from strength training plus eating in line with your goal.
If you feel bigger at first
In the first weeks, muscles hold more water and glycogen, and fat loss may not have caught up yet. Measure over two or three months before drawing conclusions, and adjust your food if needed.
Put it into practice
About this guide
STARK editorial guide. Examples explain how to use the library and record training; they are not individual coaching.
Training principles: Roberts, Nuckols & Krieger (2020), Journal of Strength and Conditioning Research — sex differences in resistance training.
The session examples come from the STARK program catalogue linked above.