What happens to your hormones when you lift weights

Written by Otaniyien Ekiomado

Strength training doesn’t just build muscle – it reshapes your internal systems. When you lift weights, your hormones adapt to help you grow stronger, recover faster, and feel better day to day.

Why hormones matter in strength training

Hormones act as messengers in your body, controlling everything from muscle growth and fat metabolism to energy levels and mood. Strength training positively impacts these hormones, helping you recover more effectively, build lean muscle, and feel more energised.

Let’s look at how different hormones respond to strength training, and how that helps you achieve better results.

How testosterone supports muscle repair and growth

Testosterone is known for its muscle-building effects, playing a central role in muscle repair and protein synthesis. Strength training, especially when focused on compound lifts like squats and deadlifts, can naturally increase testosterone production.

While testosterone levels are typically higher in men, women also benefit from this hormonal response. Increased testosterone helps improve muscle mass, strength, and overall energy, making it a valuable part of any training plan.

Why growth hormone matters for recovery and fat loss

Growth hormone (GH) supports tissue repair, fat metabolism, and muscle development. High-intensity strength training is a reliable way to trigger its release. GH also stimulates the production of another important hormone – IGF-1 – which further promotes muscle growth.

The combination of GH and IGF-1 enhances your body’s ability to repair muscle fibres after training, speeding up recovery and supporting long-term progress.

The role of IGF-1 in building muscle

Insulin-like growth factor 1 (IGF-1) works closely with growth hormone to drive muscle growth. After strength training, IGF-1 helps rebuild and strengthen the muscle fibres broken down during exercise.

This hormone plays a vital role in increasing muscle size and performance, especially when supported by consistent training and proper nutrition.

What you need to know about cortisol and training stress

Cortisol rises in response to physical stress – like intense training – and helps mobilise energy for your workout. But if cortisol stays elevated for too long, it can lead to muscle breakdown and fatigue.

Strength training that’s well-structured, combined with good sleep and recovery habits, helps keep cortisol levels in check. The goal is to use cortisol to your advantage without allowing it to interfere with recovery.

How strength training helps balance oestrogen

For women, oestrogen plays a key role in muscle function, joint health, and fat metabolism. Strength training can help regulate oestrogen levels by reducing excess body fat and encouraging hormonal balance.

Building muscle through resistance training also improves bone density and supports overall wellbeing – making it especially valuable for women of all ages.

How strength training affects hunger and appetite hormones

Leptin and ghrelin help manage hunger and fullness. Leptin signals satiety (telling you when to stop eating), while ghrelin triggers hunger.

As you build more muscle and improve your body composition, your sensitivity to leptin increases, and ghrelin levels may stabilise. This supports better appetite control and makes it easier to maintain healthy eating habits alongside training.

The connection between thyroid function and muscle mass

Your thyroid regulates metabolism, and strength training helps keep these hormones functioning well. As muscle mass increases, so does your resting metabolic rate – meaning your body uses more energy, even at rest.

Regular resistance training may also prevent the natural decline in thyroid activity that can occur with age, supporting long-term energy and vitality.

A personal training approach that supports hormonal health

At Feel Good Personal Training, we understand that fitness isn’t just about appearances. It’s about building strength from the inside out – including your hormonal health. We take a personalised approach to training, balancing intensity, rest, and nutrition to help you feel your best.

Whether you’re just getting started with strength training or looking to push your progress further, we can help you create a plan that fits your goals and supports long-term health.

Ready to get stronger and feel more balanced?

If you want to improve your muscle strength, balance your hormones, and feel more energised, strength training is one of the most effective tools available. Get in touch today to find out how we can help you build a training plan that supports your body – inside and out.