Antonia Kidman, 48, looks exhausted after his training

Is everything alright? Antonia Kidman, 48, looks exhausted as she shows her extremely slim and muscular body after a workout in the gym

Daily Mail Australia Reporter

She is known for her dedication to fitness, but did Antonia Kidman take her training regime too far?

The 48-year-old seemed to have hit the treadmill a little too hard on Boxing Day when she got out of a Sydney gym and looked completely exhausted.

The mother of the six, who is the younger sister of actress Nicole Kidman, seemed red and sweaty as she walked through the parking lot.

Tired? Antonia Kidman, 48, looked red when she left a gym in Sydney on boxing day

Tired? Antonia Kidman, 48, looked red when she left a gym in Sydney on boxing day

Her noticeably skinny limbs could be seen in a tank top and thin gym shorts.

She had her brunette locks bound in a messy ass and was completely without make-up.

Despite her healthy lifestyle, Antonia's sister Nicole is reportedly concerned about her recent weight loss.

Sweaty: the 48-year-old looked exhausted, undoubtedly as a result of a strenuous gym class

Sweaty: the 48-year-old looked exhausted, undoubtedly as a result of a strenuous gym class

Sweaty: the 48-year-old looked exhausted, undoubtedly as a result of a strenuous gym class

Sweaty: the 48-year-old looked exhausted, undoubtedly as a result of a strenuous gym class

Sweaty: the 48-year-old looked exhausted, undoubtedly as a result of a strenuous gym class

The 48-year-old has been photographed several times over the past few weeks and looks slim and exhausted, which apparently caused Nicole to worry that stress might demand the toll of the TV presenter.

Nicole starts to worry that she has done it too far and that she needs to relax and slow down her health and exercise regime a week ago, told a source about New Idea.

Antonia, who has six children, is a well-known proponent of healthy eating and fitness.

Slim: her tight, skinny limbs were fully exhibited in a sporty tank top and a thin pair of gym shorts

Slim: her tight, skinny limbs were fully exhibited in a sporty tank top and a thin pair of gym shorts

Slim: her tight, skinny limbs were fully exhibited in a sporty tank top and a thin pair of gym shorts

Of course: she had her brunette locks bound in a messy ass and was completely make-up free

Of course: she had her brunette locks bound in a messy ass and was completely make-up free

Of course: she had her brunette locks bound in a messy ass and was completely make-up free

Of course: she had her brunette locks bound in a messy ass and was completely make-up free

Of course: she had her brunette locks bound in a messy ass and was completely make-up free

The media personality has told nature and health that she likes vegetables and salads and that she walks or swims every morning.

It has been a challenging few years for Antonia, whose father Antony died in 2014.

Her first husband Angus Hawley, whom she divorced in 2007, died the following year.

Worried? Despite her healthy lifestyle, Antonia's big sister Nicole Kidman is reportedly concerned about her recent weight loss

Worried? Despite her healthy lifestyle, Antonia's big sister Nicole Kidman is reportedly concerned about her recent weight loss

Worried? Despite her healthy lifestyle, Antonia's big sister Nicole Kidman is reportedly concerned about her recent weight loss

Tense: the mother of the six wore a tense expression as she wore her sports bag

Tense: the mother of the six wore a tense expression as she wore her sports bag

Tense: the mother of the six wore a tense expression as she wore her sports bag

Tense: the mother of the six wore a tense expression as she wore her sports bag

Tense: the mother of the six wore a tense expression as she wore her sports bag

According to New Idea, Nicole is concerned that the stress & sadness & # 39; of the dead, as well as Antonia's frantic private life and career, have led to her weight loss.

Antonia spoke about how she and her children experienced the death of Angus in 2015, in an interview with The Australian Women & # 39; s Weekly.

"We just work through it together, through the tears," she told the magazine.

& # 39; I only know that my father died and then their father died. I can support them and be there because I know what they are going through. & # 39;

Muscular: the toned legs and muscular arms of the brunette were at full speed as she marched the footpath to her car

Muscular: the toned legs and muscular arms of the brunette were at full speed as she marched the footpath to her car

Muscular: the toned legs and muscular arms of the brunette were at full speed as she marched the footpath to her car

.